Unit tests coverage for plugins and classes in main

[stolen-smile]

Description:

• Found and fixed a bug in the google plugin name. Instead of googles, now it's google.
• Implemented unit tests for myparser class in EmailHarvester.py
• Implemented unit tests for EmailHarvester class in EmailHarvester.py
• Implemented unit tests for ask plugin
• Implemented unit tests for baidu plugin
• Implemented unit tests for bing plugin
• Implemented unit tests for dogpile plugin
• Implemented unit tests for exalead plugin
• Implemented unit tests for github plugin
• Implemented unit tests for google plugin
• Implemented unit tests for googleplus plugin
• Implemented unit tests for instagram plugin
• Implemented unit tests for linkedin plugin
• Implemented unit tests for reddit plugin
• Implemented unit tests for twitter plugin
• Implemented unit tests for yahoo plugin
• Implemented unit tests for youtube plugin