Add influx v2 output plugin (#4645)

plugins/outputs/influxdb_v2/README.md

@@ -0,0 +1,51 @@
+# InfluxDB Output Plugin
+
+This InfluxDB output plugin writes metrics to the [InfluxDB 2.0](https://github.com/influxdata/platform) HTTP service.
+
+### Configuration:
+
+```toml
+# Configuration for sending metrics to InfluxDB 2.0
+[[outputs.influxdb_v2]]
+  ## The URLs of the InfluxDB cluster nodes.
+  ##
+  ## Multiple URLs can be specified for a single cluster, only ONE of the
+  ## urls will be written to each interval.
+  urls = ["http://127.0.0.1:9999"]
+
+  ## Token for authentication.
+  token = ""
+
+  ## Organization is the name of the organization you wish to write to.
+  organization = ""
+
+  ## Bucket to the name fo the bucketwrite into; must exist.
+  bucket = ""
+
+  ## Timeout for HTTP messages.
+  # timeout = "5s"
+
+  ## Additional HTTP headers
+  # http_headers = {"X-Special-Header" = "Special-Value"}
+
+  ## HTTP Proxy override, if unset values the standard proxy environment
+  ## variables are consulted to determine which proxy, if any, should be used.
+  # http_proxy = "http://corporate.proxy:3128"
+
+  ## HTTP User-Agent
+  # user_agent = "telegraf"
+
+  ## Content-Encoding for write request body, can be set to "gzip" to
+  ## compress body or "identity" to apply no encoding.
+  # content_encoding = "gzip"
+
+  ## Enable or disable uint support for writing uints influxdb 2.0.
+  # influx_uint_support = false
+
+  ## Optional TLS Config for use on HTTP connections.
+  # tls_ca = "/etc/telegraf/ca.pem"
+  # tls_cert = "/etc/telegraf/cert.pem"
+  # tls_key = "/etc/telegraf/key.pem"
+  ## Use TLS but skip chain & host verification
+  # insecure_skip_verify = false
+```