Added maximum length to content field of the Comment Entity and revised the validation
Added maximum length for the title and content fields of the Issue entity
Organized imports
Added util function to IssueState enum to convert from String, and now the the constructor of IssueStateQueryFilter is using it
Added maximum length to the field name of the Label entity
Organized imports and formated the code of the User entity
Merge remote-tracking branch 'origin/master'