configure.ac,src/Makefile.am: Probe for libproj.
src/aven.cc: Fix to build with wxMSW 2.9.5.
src/img.c,src/netbits.c: Fix // comments in C code for portability
to pre-C99 compilers which don't support these as an extension.
make_release: Prefer a hand-installed 2.9 mingw build of wx to a
packaged 2.8 build.
Makefile.am,doc/HACKING.htm,lib/,survex.iss.in: Upgrade to newer
innosetup version.  Upgrade details of how to do a Microsoft Windows
build.
configure.ac,src/moviemaker.cc,src/moviemaker.h: Update movie export
code to work with latest libav API.
src/gfxcore.cc,src/moviemaker.cc,src/moviemaker.h: Improve reporting
of errors during the process of exporting a movie.
src/cad3d.c: Make --marker-size work for Skencil and SVG output.
src/cad3d.c: Correct long option names in code comment.
configure.ac,src/moviemaker.cc: Use avcodec_free_frame() if it's
available.