Support matching by multiple annotation values

[metlos]

Currently Classif only support matching an annotation attribute using its single value, e.g.:

@API(status != STABLE) ^*;

It would be nice if we could say:

@API(status != STABLE & MAINTENANCE)

or

@API(status = EXPERIMENTAL | INTERNAL)

To be correct in the logical sense we should support both AND and OR as the "contatenators" of the individual values.

This should also be used in the default values matching.