Release 0.5.2 - Bunch of bugfixes

• Bugfixes:
  • Change tar detection order to support NetBSD 'gtar'. Closes #24
  • Trick 'git-apply' when applying patches on nested Git checkouts. [larskanis]
  • Respect ENV's MAKE before fallback to 'make'. [larskanis]
  • Respect ENV's CC variable before fallback to 'gcc'.
  • Avoid non-ASCII output of GCC cause host detection issues. Closes #22