Remove DEBUG flags
Make packets slightly bigger (8972 -> 9200)
Add various BF decoders (written by SimonR?)
Keep fprintf %s argument happy
Pick middle half of band instead of first half

This removes the transpose for default halfband capturing and
fixes the band offset so that it ranges from 0.25 to 0.75 of the
band instead of 0 to 0.5.
Write to subdirectory in on data drives

Write the beamformer output files to /data1/latest and /data2/latest
directories. This allows "latest" to be a link to separate output
directories per observation in order to group related output files
together.
Ignore output products and backups
Rework of bf_decode code to include environment variable configuration

Added the following environmental variables to allow the defaults
to be overriden:

PREFIX - change the filepath prefix (default /data2/latest)
FULLBAND - record entire band instead of inner 50% (default 0)
TRANPOSE - tranpose time frequency blocks from correlator (default 0)

e.g.

 $ PREFIX=/home/kat/data TRANPOSE=1 speadrx -d bf_decode.so

The restriction on a specific beam has also been removed and bf_decode
will now record any beamformer data arriving on the specified port.
Removed dangling references to obsolete BF modules
upgrades
Merge branch 'beamformer' of github.com:ska-sa/spead

Conflicts:
	gpu/Makefile
	src/Makefile
	utils/Makefile