This patch fixes all the leftovers from the include cleanup campaign. There
were not that many (~400 entries in ~150 files) but it was definitely worth
doing it as it revealed a few duplicates.
This one is particularly tricky to move because everyone uses it
and it depends on a lot of other types. For example it cannot include
arg-t.h and must absolutely only rely on forward declarations to avoid
dependency loops between vars -> sample_data -> arg. In order to address
this one, it would be nice to split the sample_data part out of sample.h.
It was moved as-is, except for extern declaration of pattern_reference.
A few C files used to include it but didn't need it anymore after having
been split apart so this was cleaned.
The STATS_DEFAULT_REALM and STATS_DEFAULT_URI were moved to defaults.h.
It was required to include types/pattern.h and types/sample.h since they
are mentioned in function prototypes.
It would be wise to merge this with uri_auth.h later.
