Correct return type of hash_counting_table_dec()
Clarify internal variable name in hash_counting_table methods
Improved name for hash_counting_table in unittest
Make hash_counting_table_inc() return count for consistency
Add doxygen strings for hash_counting_table
Remove unnecessary pointer->uint cast (it was already a uint)
Merge branch 'hash_counting_table_inc'

Hash counting table increment now returns count.

Pull request #2: https://github.com/foolswood/adifflib/pull/2

Snuck in the discussed cast removal prior to merge.