Remove gitter links.

Author: brocaar

CONTRIBUTING.md

@@ -4,7 +4,6 @@ There are a couple of ways to get involved:
 
 * Join the discussions:
     * LoRa Server project forum [https://forum.loraserver.io/](https://forum.loraserver.io/)
-    * LoRa Gateway Config Gitter chat [https://gitter.im/loraserver/lora-gateway-bridge](https://gitter.im/loraserver/lora-gateway-bridge)
 * Report bugs or make feature-requests by opening an issue at [https://github.com/brocaar/lora-gateway-bridge/issues](https://github.com/brocaar/lora-gateway-bridge/issues)
 * Help fixing issues or improve documentation by creating pull-requests
 

README.md

@@ -1,7 +1,6 @@
 # LoRa Gateway Bridge
 
 [![Build Status](https://travis-ci.org/brocaar/lora-gateway-bridge.svg?branch=master)](https://travis-ci.org/brocaar/lora-gateway-bridge)
-[![Gitter chat](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/loraserver/lora-gateway-bridge)
 
 LoRa Gateway Bridge is a service which abstracts the 
 [packet_forwarder UDP protocol](https://github.com/Lora-net/packet_forwarder/blob/master/PROTOCOL.TXT)
@@ -30,7 +29,6 @@ project.
 * [Contributing](https://docs.loraserver.io/lora-gateway-bridge/community/contribute/)
 * Support
   * [Support forum](https://forum.loraserver.io)
-  * [Support chat](https://gitter.im/loraserver/lora-gateway-bridge)
   * [Bug or feature requests](https://github.com/brocaar/lora-gateway-bridge/issues)
 
 ## Sponsors

docs/content/community/contribute.md

@@ -12,7 +12,6 @@ There are a couple of ways to get involved:
 
 * Join the discussions:
     * LoRa Server project forum [https://forum.loraserver.io/](https://forum.loraserver.io/)
-    * LoRa Gateway Config Gitter chat [https://gitter.im/loraserver/lora-gateway-bridge](https://gitter.im/loraserver/lora-gateway-bridge)
 * Report bugs or make feature-requests by opening an issue at [https://github.com/brocaar/lora-gateway-bridge/issues](https://github.com/brocaar/lora-gateway-bridge/issues)
 * Help fixing issues or improve documentation by creating pull-requests