[FEATURE] Converting the members of GenomicRegion to __int32.
[FIX] Fixing issue with INVALID_ID in genomic_region.h
[FIX] Some more type changes for GenomicRegion::rID/beginPos/endPos.
Merge pull request #736 from holtgrewe/feature/int32-genomic-region

Changing position types in GenomicRegion to __int32