CLDCONNECT-2141-Updated Connector & Test Cases according to Certification Guidelines

As a part of the connector certification, the following issues have been fixed.

1. Upgraded Apache Chemistry Version to 0.10.0 and Alfresco Extension to 0.7
2. Fixed Blocker & Critical Issues reported via Sonar.
3. Added mock test to verify the connector.
4. Fixed failing functional test cases.
5. Fixed the demo project
6. Updated sample.md.
CLDCONNECT-2141- Updated connection error handling
Merge pull request #16 from mulesoft/feature/CLDCONNECT-2141-Certify_Connector

CLDCONNECT-2141- Updated connector to be in compliance with Certification Guidelines