#107 added severity support for concepts
#107 modified documentation
Merge pull request #125 from aparnachaudhary/severity-patch

severity support for concepts and documentation update
#71 remove redundant rule definitions
#71 added ability to get the JQAssistant version (from a service);
#71 avoid the "stream already closed" exception;
#71 in the analysis part we can now execute groups;
#123 simplify plugin API
Merge remote-tracking branch 'origin/master'
#71 changed filtering of properties;
Merge remote-tracking branch 'origin/master'
#71 fixed reading of the properties file;
#71 first draft of Selenium tests;
Merge remote-tracking branch 'origin/master'
#71 test cleanup