Separate yparser
This is an attempt to unloop the library dependency loop.
- libknot-int is now standalone library and no symbols from libknot are used.
- libknot depends on libknot-int
- libknot-yparser depends on libknot and libknot-int
@dsalzman and @jvcelak please review.
As a side note - I think there should be a libknot/libknot.h that would be enough to include in any project using libknot, dtto for libdnssec...
Edit: there is libknot/libknot.h, it's just not used that much...