Update to 0.77

Upstream changes:
Version 0.77 (2015-07-22)
-------------------------

* ensure consistent order of enums when generating code; this was
  a real bug and caused the configuration part of C::B::C to report
  wrong (even invalid) configurations back to the user when built
  using a recent version of Perl that randomises hash keys

* fix cpan #85264: the POD test was reporting a missing =back tag
  in one of the support modules; the ultimate fix was to ensure only
  the provided modules were POD checked

* fix cpan #83167: an artificially low refcnt for immortal variables
  introduced recently for debug Perl builds was causing the refcnt
  tests to fail for SvNULLs; thanks to Reini Urban for his patch;
  also thanks to Nicholas Clark for pointing me to the Perl commit

* fix cpan #78165: spelling errors in the documentation; thanks to
  gregor herrmann for providing a patch

* fix deprecated use of unescaped braces in regex

* fix some gcc and Perl warnings

* switch from SnapshotCM to git repo: github.com/mhx/Convert-Binary-C/

(wen)