PATCH: Add threaded tests

[Loren James Rittle]

OK, a full bootstrap and check cycle completed on an MP
sparc-sun-solaris2.7 machine.  As I hoped, it does find:

FAIL: thread/pthread3.cc execution test

since even though the testcase itself was built at -O0, the library
code was built at -O2 due to it being built during a full bootstrap.

I am working on getting patch into tree today for this issue.  I will
also take the other threaded locale issue that just poped up. ;-)

Regards,
Loren