#99 Added ability to include more storage options for authentication

We refactored the current storage solution, as it is limited to file storage only. It now 

a) provides several adapters to use either file storage or redis (added ability to add more in future) for authentication
b) does not use instance variables from other classes, uses methods instead

Added specs for all refactored code. Old FileStorage Class has been refactored to use the new Adapters, you might want to mark it as deprecated. Cleaned gemspec to not include all files manually, if you want to exclude some files, you can use the exclude flag for this.

This code has been tested to work with your drive examples and does not break.