[Halld-offline] c++11 features in gcc 4.4.6 and gcc 4.4.7

[David Lawrence]

Hi All,

  FYI: I just made a branch "davidl_gcc4.4_c++11” that adds the -std=c++0x compiler argument
by default when using gcc 4.4.6 or 4.4.7. These are the default compilers on CentOS6. This gives
access to some features of C++11 (e.g. threads) that were available in the gcc 4.4 compilers.
I’ve not submitted a pull request just yet since this seems like something people might want to
discuss before implementing in the master. In the meantime, if anyone is interested in testing
this out, please go ahead and do so.

Regards,
-David