runtime: make sure we are calling from pmt namespace.
fixup.
blocks: remove use of assertGreater in test to go back to support Python 2.5.
runtime: (re)creating a pmt shared lib to link against.

This fixes a bug between versions of loaders that pull in the PMT
definitions differently. The symptom is a problem in gr_block_registry
where it creates a PMT dictionary before PMT pointers are known, so
the dictionary's intrusive pointer is invalid.
digital: OFDM frame equalizer now as an option to work w/o len tag
digital: fix some issues w/ header parser/gen; QA, wrong OFDM symbol number calculation, bug that always returns PMT_NIL
digital: merge from master
Merge remote-tracking branch 'tom/next' into next

Conflicts:
	gnuradio-runtime/lib/pmt/CMakeLists.txt
Merge remote-tracking branch 'martin/next-ofdmfix' into next