Update Makefile.offline_tutorial_test: reverting a change that cut down on run time, but broke gstlal_inspiral_plot_background

inspiral.py, lloidhandler.py: only provide sub-threshold snr time series if the detector is on at coalescence (Jolien's review request)

gstlal_ll_inspiral_pipe: reduce number of aggregator jobs, rewrite portion that divvies up which jobs aggregators process

This reverts commit f8093c93.

gstlal_ll_inspiral_pipe: support external kafka service, remove daily pages - they will be replaced scale out aggregators as future proofing

inspiral.py: Fix bug in subthreshold trigger channel name, and get rid of some setattr()s and getattr()s

Update inspiral.py: replace the file tag "ranking statistic" to "ranking_statistic" since gracedb doesn't allow spaces in tag names. This change will fix the multiple failed uploads to gracedb. 

- support older version of pandas

svd_bank_snr.py: simplify the program and change FIR_SNR to calculate the modulus of the complex snr

gstlal_inspiral_calc_snr: make corresponding changes

svd_bank_snr: In mode 1, use mkwhitened_multirate_src instead of mkwhiten

- refactor as a template-generating class and wrapper function so that the whitening and shifting can be reproduced by other code