Merged r10554:10595 from michaelld/am_swig_4 into trunk. Major overhaul of SWIG usage in build system, also fixes ticket:130. Trunk passes distcheck.

git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@10596 221aa14e-8319-0410-a670-987f0aec2ac5