gstlal_inspiral_postcohspiir_lvalert_plotter: add test code to make sure the corresponding lvalert program will be executed for a given trigger.This is to avoid clashes of several lvalert
programs listening to the same node.

update the xml reading functions to use glib functions for simplicity

 combine of commit 0d4ae170 and 5ba71df7:
    cbc_template_iir.py: add epoch_index to record the epoch time relative to the
    end time which will be used to adjust the reported trigger end time;
    update the autocorrelation function for cut off templates so the autocorrelation = crosscorr(cut_template, full-length tempalte);
    update the matched_filter function to give warnings to incontinous data
replace the old method that generates sigmasq using lalfft with numpy.fft

update the matched_filter function to incorporate negative latency option;
fix a bug in the above function to pad zeros into gaps of data. This fixed the peak L1 SNR time for the GW170817

Apply a simple cut of triggers before uploading them to GraceDB. In implementation, check if any event has a FAR less than 1e-6Hz. If so, examine if its coherent network SNR is less than a defined value (default is 8). If so, do not upload it to GraceDB.

fix a bug to prevent single detector FAR overflow

gstlal_inspiral_postcohspiir_lvalert_plotter: changed an option that read from input instead from the gracedb event file. This is required by the new sky map generation code that splits two coeff files.

remove share/configs/ER14/fix, see branch spiir for that

postcoh_finalsink.py: turn off skymap generation from inside pipeline; do it using lvalert from gracedb

    fix the SNR=0 and coa_phase=nan issue by checking the individual SNRs of each ifo in trigger->ifos;
    if single SNR < EPSILON (1e-6), remove this ifo from trigger->ifos

1. --output-coh-coeff: U and diff arrays for calculating coherent SNR;
2. --output-prob-coeff: Det arrays for calculating prob skymap;
reduce the latency from loading three arrays to only loading Det array for prob skymap calculation (4s->about 1s)

gstlal_postcoh_skymap2fits: load detrsp map once instead of 3 times, save 4*2 seconds now it costs 1.5s for import and 4s for loading the map. This 4s can be further
saved by using a smaller map only containing the Det array

rank fap is a single-precision value in the postcoh table. restrict its minimal value to be FLT_MIN

gstlal_inspiral_postcohspiir_plotsummary: remove far if None; display Virgo snr and chisq for noninj output