support a no-dbghelp (ideally no-priv-lib-at-all) drmem build to avoid priv lib bugs

_From [bruen...@google.com](https://code.google.com/u/109494838902877177630/) on November 14, 2012 12:17:11_

we've seen many private library bugs recently:
- issue #1067 + DRi#963
- DRi#964
- DRi#967
- DRi#977
- DRi#915

perhaps long-term DRi#916 can address these, but for now these are causing
stability issues on large apps.

multiple times while debugging the above issues I've hacked together a
drmemorylib that has no dbghelp and no kernel32. this issues is about
making that an official build, and further adding post-processing support
( issue #446 ) and pre-generation of symcaches to find all the static libc
addresses ( issue #192 ) for fully functional execution.

_Original issue: http://code.google.com/p/drmemory/issues/detail?id=1084_