Squash/rebased martin/ofdm-master onto trial merge branch

Conflicts:
	gr-blocks/include/blocks/CMakeLists.txt
digital: fix QA tests for pmt import
analog: minor cleanup for added block
blocks: minor cleanup of added blocks
digital: fixed tagged_stream_mux xml and example GRC app
blocks: adding correct link flags for log4cpp
core: adding default empty tags list argument to vector_source_x.set_data() function to unbreak old calls
blocks: moving copy, endian_swap, head, skiphead, vector_source/sink/insert to gr-blocks.
blocks: moved nop, null source/sink, copy, vector_map to gr-blocks.
blocks: changing vector_insert category location.
Merge branch 'master' of gnuradio.org:gnuradio
digital: removed superfluous fftshift
digital: cleaned out debugging blocks
docs: Adding gr-uhd to sphinx docs.
sphinx docs: Added additional block function names to blacklist so that they are not displayed for every block.
Merge branch 'maint'
Merge remote-tracking branch 'martin/master-cleanup'
core: fix typo in logger header file
blocks: moved lfsr and friends to gr-blocks.
core: add missing include dir