Fixing umask issue with file cache
Adding most of the tagging support to the file cache
Fixing issue where tag file is left behind after deleting a key in file cache
Adding removeByTags functionality to file cache (tests fail)
Adding sanity check before deleting tag file
Fixing issues with file cache engine and tagging
Adding test for multiple tagged item deletion and fixing breaking issues with tagging
Adding function to travis build script for creating cache directory
CS fixes