Created Notify_fcm (markdown)

Notify_fcm.md

@@ -0,0 +1,42 @@
+## Firebase Cloud Messaging (FCM)
+* **Source**: https://aws.amazon.com/sns/
+* **Icon Support**: No
+* **Message Format**: Text
+* **Message Limit**: 160 Characters per message
+
+### Account Setup
+You'll need to create an account with Google's Firebase Cloud Messaging Service (FCM) first to use this.
+
+This plugin uses the **HTTP v1 API** and NOT the **Legacy HTTP API** service.  [See here](https://firebase.google.com/docs/cloud-messaging/migrate-v1#update-authorization-of-send-requests).
+
+### Syntax
+Valid syntaxes are as follows:
+* **fcm**://**{Project}**@**{APIKey}**/**{Device}**
+* **fcm**://**{Project}**@**{APIKey}**/**{Device1}**/**{Device2}**/**{DeviceN}**
+* **fcm**://**{Project}**@**{APIKey}**/#**{Topic}**
+* **fcm**://**{Project}**@**{APIKey}**/#**{Topic1}**/#**{Topic2}**/#**{TopicN}**
+
+You can mix and match these entries as well:
+* **sns**://**{Project}**@**{APIKey}**/**{Device1}**/#**{Topic1}**
+
+### Parameter Breakdown
+| Variable        | Required | Description
+| --------------- | -------- | -----------
+| Project         | Yes      | The generated _Project ID_ from the FCM Management Console
+| APIKey          | Yes      | The generated _API Key_ from the FCM Management Console
+| Device          | No       | The device you wish send your message to
+| Topic           | No       | The topic you want to publish your message to.
+
+**Note:** This notification service does not use the title field; only the _body_ is passed along.
+
+#### Example
+Send a FCM notification:
+```bash
+# Assuming our {Project} is Apprise
+# Assuming our {APIKey} is bu1dHSdO22pfaaVy
+# Assuming our {Device} - ABCD:12345
+
+apprise -vv -t "Test Message Title" -b "Test Message Body" \
+   fcm://Apprise@bu1dHSdO22pfaaVy/ABCD:12345
+
+```