Fix some last upstream changes that break the build.

  The LLVM_ENABLE_CXX11 cmake option is needed now.
  Add a patch to fix: no sin_len in sockaddr_in structure on linux.
  Add a patch to fix: inconsistent invocation of python in build-swig-Python.sh.
Merge pull request #1 from xdegaye/master

Fix some last upstream changes that break the build.