Merge pull request #81 from sduran/master

Add a configuration option to change the database field containing the password
Maintain backwards compatibility
Correctly check for null

protects against the unlikely column named false.
Properly protects against the false column name
Created a Repository to abstract any database interaction
Hardcore TDD action on ConfideRepository
Password reminder related methods in the repository
Delegating responsabilities
Added homepage to composer.json
Renamed ConfideRepositoryTest
Use ConfideRepository in main Confide class
Improved test code
More adjustments regarding the use of repository and improved test coverage