Thingsboard-gateway

Minor release with the following improvements.

**Main features:**
* [CAN Connector] Adding CAN bus connector, thanks to anonymous contributor;

**Improvements:**
* [Modbus Converter] Improvements in processing data;
* [Modbus Connector] Added more configuration parameters in the configuration file to increase flexibility (*parity*, *bytesize*, *stopbits*, *strict* mode activation (Use Inter char timeout for baudrates <= 19200)) 266 ;
* [TB Client] Imrovements in connection to the ThingsBoard;
* [Request Connector] Added feature of processing array in response(If response is an array of objects, each element will be processed as an independent object);

**Bug fixes:**

* [Modbus Connector] Fix for 266 ;
* [Installation] Fix for 265, Thanks for investigations to pehedima;
* [TB Gateway Service] Fix for deadlock on telemetry uploading;

* [**Request Connector**] Added feature of processing array in response.

* Fix for deadlock on uploading telemetry.

Minor release with the following improvements.

**Improvements:**
* [Connectors] Improvements to RPC requests and attribute update requests processing;
* [TB gateway service] Improvements in configuration processing;
* [Request Connector] Improvements for data processing from external API;
* Code refactor.

**Bug fixes:**

* [Modbus Connector] Fix for 262;
* [Modbus Connector] Fix for 261;
* [Custom serial connector] Fix for device processing;

**Fixes and improvements**:
- Minor fixes for Modbus Connector
- Partial refactoring of the gateway service.

Fixes:
- Fix for 255 Resolved issue with expressions in the converter.