add influxdb spec (#754)

concepts/bindings/README.md

@@ -31,6 +31,7 @@ Every binding has its own unique set of properties. Click the name link to see t
 | [Twilio](../../reference/specs/bindings/twilio.md)       |    | ✅ | Experimental |
 | [Twitter](../../reference/specs/bindings/twitter.md)       | ✅ |  | Experimental |
 | [SendGrid](../../reference/specs/bindings/sendgrid.md)       |    | ✅ | Experimental |
+| [InfluxDB](../../reference/specs/bindings/influxdb.md)       |    | ✅ | Experimental |
 
 ### Amazon Web Service (AWS)
 

reference/specs/bindings/influxdb.md

@@ -0,0 +1,31 @@
+# InfluxDB Binding Spec
+
+```yaml
+apiVersion: dapr.io/v1alpha1
+kind: Component
+metadata:
+  name: <NAME>
+  namespace: <NAMESPACE>
+spec:
+  type: bindings.influx
+  metadata:
+  - name: url # Required
+    value: <INFLUX-DB-URL>
+  - name: token # Required
+    value: <TOKEN>
+  - name: org # Required
+    value: <ORG>
+  - name: bucket # Required
+    value: <BUCKET>
+```
+
+- `url` is the URL for the InfluxDB instance. eg. http://localhost:8086
+- `token` is the authorization token for InfluxDB.
+- `org` is the InfluxDB organization.
+- `bucket` bucket name to write to.
+
+> **Note:** In production never place passwords or secrets within Dapr components. For information on securely storing and retrieving secrets refer to [Setup Secret Store](../../../howto/setup-secret-store)
+
+## Output Binding Supported Operations
+
+* create