Revision 1879245

Merge r1876662 from trunk:

 * r1876662
   Avoid check for SWIG version for Python bindings when --without-swig is
   passed.
   Justification:
     SWIG python bindings should be able to be built without SWIG when we use
     the release tarball
   Votes:
     +1: futatuki, stsp, rhuijben