pass fingerprint reason (int) for advanced functionality

[ndori]

pass some raw data in case we want to use it, it might be a use case the library does not cover which will not cause it to be useless.

e.g. FINGERPRINT_ACQUIRED_GOOD... , FINGERPRINT_ERROR_UNABLE_TO_PROCESS, and so on.

In most case it won't be used but that's an important data that might be used

[Mauin]

I thought about this initially when designing this library and decided against this to make it as easy as possible to use the fingerprint APIs without having to touch too much of the internals and the states that you mention.

However especially with the new FingerprintDialog also providing states such as FINGERPRINT_ERROR_NO_FINGERPRINTS I can see the added benefit in this and I'll consider it for v3.

This also relates to #89