blocks: pdu_filter, add option for filter match inversion
digital: Fix alloc bug in HDLC deframer and make Coverity happy.
pmt: adding pmt.uniform_vector_itemsize(pmt_t vector), returns the size per item in bytes within a uniform vector for any kind of uniform vector
cmake: fix FindPortaudio pkg-config support

Look for portaudio-2.0 which is the standard pkg-config name for the
portaudio API that gnuradio requires.  Correct the variable name in the
include directory hint derived from pkg-config information.

Signed-off-by: Peter A. Bigot <pab@pabigot.com>
cmake: fix FindPortaudio to reject unsupported API version

portaudio18 passes the generic test for locating portaudio, but will
fail when building gr-audio.  Test for the failure before accepting the
portaudio that was found.

Signed-off-by: Peter A. Bigot <pab@pabigot.com>
filter: fix broken backported QA test in channelizer
utils: Added try: clause for SWIG import, fixing python-only OOT modules

__init__.py used to throw an ImportError when trying to load
a python-only OOT module.
Merge branch 'maint'

Conflicts:
	gr-filter/python/filter/qa_pfb_channelizer.py
Merge remote-tracking branch 'osh/pdu_filter_inversion'
Merge remote-tracking branch 'bistromath/hdlc_fix'
Merge remote-tracking branch 'osh/pdu_uvector_itemsize'