Add request for sample queries (#1608)

plugins/inputs/EXAMPLE_README.md

@@ -27,6 +27,14 @@ The example plugin gathers metrics about example things
     - tag2
 - measurement2 has the following tags:
     - tag3
+    
+### Sample Queries:
+
+These are some useful queries (to generate dashboards or other) to run against data from this plugin:
+
+```
+SELECT max(field1), mean(field1), min(field1) FROM measurement1 WHERE tag1=bar AND time > now() - 1h GROUP BY tag
+```
 
 ### Example Output:
 

plugins/inputs/mock_Plugin.go

@@ -6,10 +6,22 @@ import (
 	"github.com/stretchr/testify/mock"
 )
 
+// MockPlugin struct should be named the same as the Plugin
 type MockPlugin struct {
 	mock.Mock
 }
 
+// Description will appear directly above the plugin definition in the config file
+func (m *MockPlugin) Description() string {
+	return `This is an example plugin`
+}
+
+// SampleConfig will populate the sample configuration portion of the plugin's configuration
+func (m *MockPlugin) SampleConfig() string {
+	return `  sampleVar = 'foo'`
+}
+
+// Gather defines what data the plugin will gather.
 func (m *MockPlugin) Gather(_a0 telegraf.Accumulator) error {
 	ret := m.Called(_a0)