updates T4 outputs
Migrates the Contains assertions to the new error format message.

Fixes bugs related to the Contains... with null or empty values.
Renames FluentAssertion into CheckImpl.
Continues to rename/migrate from an IFluentAssertion world to a ICheck world.
Continues to rename/migrate from an IFluentAssertion world to a ICheck world.
Continues to rename/migrate from an IFluentAssertion world to a ICheck world.
Continues to rename/migrate from an IFluentAssertion world to a ICheck world.
Continues to rename/migrate from an IFluentAssertion world to a ICheck world.
Continues to rename/migrate from an IFluentAssertion world to a ICheck world.
Renames ContainsOnly to IsOnlyMadeOf and makes it succeed with empty list in order to follow the issue https://github.com/tpierrain/NFluent/issues/53
Renames ContainsOnly to IsOnlyMadeOf and makes it succeed with empty list in order to follow the issue https://github.com/tpierrain/NFluent/issues/53
Improves the release note.
Fixes typo within the release note.
Now, the NumberChecks does not implement ICheck and Co anymore. That was useless, and prevented us to have a good test coverage.
Reviewed code to improve test coverage on ExceptionHelper