ST: Research adds examples that demos pthread and helloworld. v6.0.118

[winlinvip]

1. trunk/research/st/exceptions.cpp About exceptions with ST, works well on linux and mac, not work on cygwin.
2. trunk/research/st/pthreads.cpp About pthreads with ST, works well on all platforms.
3. trunk/research/st/hello.cpp Hello world, without ST, works well on all platforms.
4. trunk/research/st/hello-world.cpp Hello world, with ST, works well on all platforms.
5. trunk/research/st/hello-st.cpp A very simple version for hello world with ST, works well on all platforms.