Add aerospike plugin support

- Does not use the aerospike client, but sends the stats command
  using the aerospike required format
- Queries available namespaces and gets stats for all of them

closes #300

plugins/aerospike/README.md

@@ -0,0 +1,265 @@
+## Telegraf Plugin: Aerospike
+
+#### Plugin arguments:
+- **servers** string array: List of aerospike servers to query (def: 127.0.0.1:3000)
+
+#### Description
+
+The aerospike plugin queries aerospike server(s) and get node statistics. It also collects stats for
+all the configured namespaces.
+
+For what the measurements mean, please consult the [Aerospike Metrics Reference Docs](http://www.aerospike.com/docs/reference/metrics).
+
+The metric names, to make it less complicated in querying, have replaced all `-` with `_` as Aerospike metrics come in both forms (no idea why).
+
+# Measurements:
+#### Aerospike Statistics [values]:
+
+Meta:
+- units: Integer
+
+Measurement names:
+- batch_index_queue
+- batch_index_unused_buffers
+- batch_queue
+- batch_tree_count
+- client_connections
+- data_used_bytes_memory
+- index_used_bytes_memory
+- info_queue
+- migrate_progress_recv
+- migrate_progress_send
+- migrate_rx_objs
+- migrate_tx_objs
+- objects
+- ongoing_write_reqs
+- partition_absent
+- partition_actual
+- partition_desync
+- partition_object_count
+- partition_ref_count
+- partition_replica
+- proxy_in_progress
+- query_agg_avg_rec_count
+- query_avg_rec_count
+- query_lookup_avg_rec_count
+- queue
+- record_locks
+- record_refs
+- sindex_used_bytes_memory
+- sindex_gc_garbage_cleaned
+- system_free_mem_pct
+- total_bytes_disk
+- total_bytes_memory
+- tree_count
+- scans_active
+- uptime
+- used_bytes_disk
+- used_bytes_memory
+- cluster_size
+- waiting_transactions
+
+#### Aerospike Statistics [cumulative]:
+
+Meta:
+- units: Integer
+
+Measurement names:
+- batch_errors
+- batch_index_complete
+- batch_index_errors
+- batch_index_initiate
+- batch_index_timeout
+- batch_initiate
+- batch_timeout
+- err_duplicate_proxy_request
+- err_out_of_space
+- err_replica_non_null_node
+- err_replica_null_node
+- err_rw_cant_put_unique
+- err_rw_pending_limit
+- err_rw_request_not_found
+- err_storage_queue_full
+- err_sync_copy_null_master
+- err_sync_copy_null_node
+- err_tsvc_requests
+- err_write_fail_bin_exists
+- err_write_fail_generation
+- err_write_fail_generation_xdr
+- err_write_fail_incompatible_type
+- err_write_fail_key_exists
+- err_write_fail_key_mismatch
+- err_write_fail_not_found
+- err_write_fail_noxdr
+- err_write_fail_parameter
+- err_write_fail_prole_delete
+- err_write_fail_prole_generation
+- err_write_fail_prole_unknown
+- err_write_fail_unknown
+- fabric_msgs_rcvd
+- fabric_msgs_sent
+- heartbeat_received_foreign
+- heartbeat_received_self
+- migrate_msgs_recv
+- migrate_msgs_sent
+- migrate_num_incoming_accepted
+- migrate_num_incoming_refused
+- proxy_action
+- proxy_initiate
+- proxy_retry
+- proxy_retry_new_dest
+- proxy_retry_q_full
+- proxy_retry_same_dest
+- proxy_unproxy
+- query_abort
+- query_agg
+- query_agg_abort
+- query_agg_err
+- query_agg_success
+- query_bad_records
+- query_fail
+- query_long_queue_full
+- query_long_running
+- query_lookup_abort
+- query_lookup_err
+- query_lookups
+- query_lookup_success
+- query_reqs
+- query_short_queue_full
+- query_short_running
+- query_success
+- query_tracked
+- read_dup_prole
+- reaped_fds
+- rw_err_ack_badnode
+- rw_err_ack_internal
+- rw_err_ack_nomatch
+- rw_err_dup_cluster_key
+- rw_err_dup_internal
+- rw_err_dup_send
+- rw_err_write_cluster_key
+- rw_err_write_internal
+- rw_err_write_send
+- sindex_ucgarbage_found
+- sindex_gc_locktimedout
+- sindex_gc_inactivity_dur
+- sindex_gc_activity_dur
+- sindex_gc_list_creation_time
+- sindex_gc_list_deletion_time
+- sindex_gc_objects_validated
+- sindex_gc_garbage_found
+- stat_cluster_key_err_ack_dup_trans_reenqueue
+- stat_cluster_key_err_ack_rw_trans_reenqueue
+- stat_cluster_key_prole_retry
+- stat_cluster_key_regular_processed
+- stat_cluster_key_trans_to_proxy_retry
+- stat_deleted_set_object
+- stat_delete_success
+- stat_duplicate_operation
+- stat_evicted_objects
+- stat_evicted_objects_time
+- stat_evicted_set_objects
+- stat_expired_objects
+- stat_nsup_deletes_not_shipped
+- stat_proxy_errs
+- stat_proxy_reqs
+- stat_proxy_reqs_xdr
+- stat_proxy_success
+- stat_read_errs_notfound
+- stat_read_errs_other
+- stat_read_reqs
+- stat_read_reqs_xdr
+- stat_read_success
+- stat_rw_timeout
+- stat_slow_trans_queue_batch_pop
+- stat_slow_trans_queue_pop
+- stat_slow_trans_queue_push
+- stat_write_errs
+- stat_write_errs_notfound
+- stat_write_errs_other
+- stat_write_reqs
+- stat_write_reqs_xdr
+- stat_write_success
+- stat_xdr_pipe_miss
+- stat_xdr_pipe_writes
+- stat_zero_bin_records
+- storage_defrag_corrupt_record
+- storage_defrag_wait
+- transactions
+- basic_scans_succeeded
+- basic_scans_failed
+- aggr_scans_succeeded
+- aggr_scans_failed
+- udf_bg_scans_succeeded
+- udf_bg_scans_failed
+- udf_delete_err_others
+- udf_delete_reqs
+- udf_delete_success
+- udf_lua_errs
+- udf_query_rec_reqs
+- udf_read_errs_other
+- udf_read_reqs
+- udf_read_success
+- udf_replica_writes
+- udf_scan_rec_reqs
+- udf_write_err_others
+- udf_write_reqs
+- udf_write_success
+- write_master
+- write_prole
+
+#### Aerospike Statistics [percentage]:
+
+Meta:
+- units: percent (out of 100)
+
+Measurement names:
+- free_pct_disk
+- free_pct_memory
+
+# Measurements:
+#### Aerospike Namespace Statistics [values]:
+
+Meta:
+- units: Integer
+- tags: `namespace=<namespace>`
+
+Measurement names:
+- available_bin_names
+- available_pct
+- current_time
+- data_used_bytes_memory
+- index_used_bytes_memory
+- master_objects
+- max_evicted_ttl
+- max_void_time
+- non_expirable_objects
+- objects
+- prole_objects
+- sindex_used_bytes_memory
+- total_bytes_disk
+- total_bytes_memory
+- used_bytes_disk
+- used_bytes_memory
+
+#### Aerospike Namespace Statistics [cumulative]:
+
+Meta:
+- units: Integer
+- tags: `namespace=<namespace>`
+
+Measurement names:
+- evicted_objects
+- expired_objects
+- set_deleted_objects
+- set_evicted_objects
+
+#### Aerospike Namespace Statistics [percentage]:
+
+Meta:
+- units: percent (out of 100)
+- tags: `namespace=<namespace>`
+
+Measurement names:
+- free_pct_disk
+- free_pct_memory