- in command line parsing, check that at least two detectors are supplied

- replace use of numpy. with math. where possible

- simplify fap_after_trials()

gstlal/bin/gstlal_fake_aligo_frames: refactor mkLLOIDbasicsrc() to take a single data_source argument

gstlal-ugly/examples/configurations/H1H2_COHERENT/coh_null_h1h2.py: refactor mkLLOIDbasicsrc() to take a single data_source argument

gstlal-ugly/bin/gstlal_ll_inspiral: refactor mkLLOIDbasicsrc() to take a single data_source argument

gstlal-ugly/bin/gstlal_iir_ll_inspiral: refactor mkLLOIDbasicsrc() to take a single data_source argument

gstlal-ugly/bin/gstlal_iir_inspiral: refactor mkLLOIDbasicsrc() to take a single data_source argument

gstlal-ugly/bin/gstlal_excesspower: refactor mkLLOIDbasicsrc() to take a single data_source argument

- add support for single-precision floats, and 8-, 16-, and 32-bit signed and unsigned ints

1. Added an option for a BBH distribution.
2. Setting a local rate to 0.0 or less will disable its generation.
3. Changed default local rates to those quoted in the rates paper.

- expose the GraceDB FAR threshold on the web server
- allow remote modification of the threshold's value

- rename methods associated with web server to make their use more obvious

- fix two typos in last commit

- make timeouts non-fatal, push heart beat buffers downstream instead

- re-organize code in create() method to reduce indentation level

- treat empty input buffers as heart beats, add code to forward 0-length
  buffers out each source pad