Add IDEA folder to gitignore
Refactor GuavaDeserializers

Templated support for all the multimap implementations. This makes it clear what this module
currently supports and what still is missing. Also better matches the inheritance structure
of Guava.
Add generic parent class for multimap deserializing
HashMultimap implementation & initial test
All new implementations working for <String, String> combo
tests are failing... even on the old code
Passing tests & updated dependencies to latest versions
actually updated dependencies and removed old code
Merge pull request #25 from mvolkhart/HashMultimap

More Multimaps