Removed unused variable
Changed the KeywordMap to use keyword and not path as key, to enable check for existing keyword
Prints a warning if a keyword that has already been added, occurs again. Next step, process keywords from several ordered, top-level folders
Created folders for keywords, these will be read in an alphanumerical sorted order. To enable organization and override of keywords.
Changed behaviour when same keyword occurs again, delete existing entry, replace with new.
Merge pull request #361 from flikka/keyword-folder

Put keywords in subfolders
Merge remote-tracking branch 'upstream/master'