Explain RTS cflags for tiny cpu.

Ignore-this: b09e6da5e1704b9da4a51ae6a23f57ee

darcs-hash:20130316172107-99646-d9545e56b6d11bf6511bf35a793f2246cae9b697.gz
Upgrade some JHC_EXT_LIBS.

Ignore-this: d51be66b69fbe0240775f1464a4d46e7

darcs-hash:20130317070629-99646-8d122ceea5273835030a18ac965842896f8f42e1.gz
Merge branch 'master' into arafura

Conflicts:
	library_deps.make
Use "JHC_XXX" name in Makefile to share source code with jhc.