gstlal_itacac.c: fix bug where you try to flush more samples than we have from an adapter in a corner case

cbc_template_fir.py: use ChiWai's implementation if pandas is available, default to Chad's implementation

	--ensuring the template autocorrelation vs time is plotted with same length.

lloidhandler.py: Make the horizon history 1 day instead of 1 week for uploads.  This reduces file size to 5 MB which is highly desirable but also doesn't detract from e.g., making plots.

- temporarily clip the horizon distance history to just the last week when
  uploading to gracedb.  this will be reverted when a more efficient
  encoding scheme can be found

- there was a time when streamthinca needed to define a special class to be
  used for triggers to allow the coincidence algorithm to work, and so it
  made sense for the definition to live in streamthinca where the
  requirements were defined.  today no special class is required, the
  underlying trigger class is simply used as-is, but code like lloidhandler
  is still importing the symbol from streamthinca instead of importing it
  themselves directly.  this patch untangles this now gratuituous
  interdependency.