Filter option names to escape symbols not allowed as C++ identifiers.
Filter option names to escape symbols not allowed as C++ identifiers.

Makes it possible to use options with names like "Wa,".
Also fixes the -Wall option handling as a side-effect.


git-svn-id: a4a6f32337ebd29ad4763b423022f00f68d1c7b7@50973 91177308-0d34-0410-b5e6-96231b3b80d8

lodyagin/bare_cxx,lodyagin/bare_cxx,lodyagin/bare_cxx,lodyagin/bare_cxx,lodyagin/bare_cxx