AppPkg: Add the Arithchk utility and clean up some build problems.

AppPkg: Add the Arithchk utility and clean up some build problems.

AppPkg\
  AppPkg.dsc
    Update copyright date
    Add Component ArithChk.inf
  Applications\
    Main\
      Main.inf
        Remove DevShell dependency
    Python\
      Python-2.7.2\Modules\
        socketmodule.c
          Initialize addro, in sock_sendto(), before use.
    ArithChk\
      ArithChk.inf
      arithchk.c
        NEW
        This is a direct port of the arithchk program which is included as part of the NetBSD gdtoa library.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by:  daryl.mcdaniel@intel.com
Reviewed-by:  Erik Bjorge <erik.c.bjorge@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16082 6f19259b-4bc3-4df7-8a09-765794883524