Merge pull request #2341 in HDFFV/hdf5 from ~DYOUNG/werror:thread_id to develop
* commit 'cefacee21b5ad569e2394b32793648e1b80f3d6b':
src/H5Eint.c: #include H5TSprivate.h for H5TS_thread_id() definitions.
Change thread IDs to uint64_t from unsigned long, per Quincey's suggestion.
Add thread_id.c to the MANIFEST and the CMakeLists.txt per Allen's request.
Replace pthread_self_ulong() with H5TS_thread_id(). The POSIX Threads implementation ought to be portable to any system that has POSIX Threads. On Windows, I use the same API call as before.