gstlal_compute_strain:  Added a trick to make it possible to high-pass filter the inverse sensing path at a lower sample rate without losing information above the Nyquist rate.

gstlal-calibration:  Many small chenges, including conditional reading in of a config file parameter in gstlal_compute_strain and DCS config file updates.

gstlal-calibration/tests/check_calibration/Makefile:  Fixed easy raw frame maker so that it only makes raw frames to fill in any gaps.

- avoid an attribute look-up inside lower_bound_in_seglist()

gstlal_compute_strain:  Better way to to check for config file options that may not be present.  New option to flip sign of the pcal channel.

This reverts commit 62952454.

ll_simplify_and_cluster.sql: delete high far events (above 1e-4) from the databases to keep the size manageable.

inspiral.py: choose only the best coinc for gracedb uploads, and fix performance issue of generating an xml doc when there are no uploads to do

gstlal_ll_inspiral_daily_page: fix some comments and comment out plot background code, which isn't working

gstlal_compute_strain:  numerous small bug fixes so that the pipeline will run with various combinations of options.  Most notably includes high-latency bug fixes.

lal_transferfunction:  Now has property parallel_mode, which when true produces output independent of start time.  This is useful for offline calibration and noise subtraction.

- add snr_min cut to remove sub-threshold triggers in case itac starts
  producing them

- use new "event_collector" feature of snglcoinc to identify singles
  suitable for use in background models.  this should fix the problem of
  the sum-of-SNR^2 cut introducing a bias into the noise model PDFs.  in
  any case it decouples background collection from other aspects of
  candidate construction, allowing for the selection criterion to be
  adjusted more easily, with less thought required.