O4a online dtdphi plotter

This patch allows the following dtdphi plot to be uploaded to gracedb page.
Example G-event pages:
MDC 3-ifo event (two dtdphi plots)
MDC 2-ifo event (one dtdphi plot)
MDC 1-ifo event (no dtdphi plot)

TODO:

• test with single triggers
• test with online small analysis
• try adding LV plot and see if that is informative any way

gstlal-inspiral/python/plots/dtdphi.py

@@ -63,8 +63,9 @@ def dtdphi2prob(dt, dphi, ifo1, ifo2, refsnr, refhorizon):
 	phi = {ifo1: 0, ifo2: dphi}
 	snr = {ifo1: refsnr[ifo1], ifo2: refsnr[ifo2]}
 	horizon = {ifo1: refhorizon[ifo1], ifo2: refhorizon[ifo2]}
+	snr_net = sum(x**2 for x in snr.values())**.5
 	# signature is (time, phase, snr, horizon)
-	p = TPDPDF.time_phase_snr(t, phi, snr, horizon) * (sum(s**2 for s in snr.values())**.5)**4
+	p = TPDPDF.time_phase_snr(t, phi, snr, horizon) * (snr_net)**4 / (snr_net / numpy.prod([x for x in snr.values()]))
 	return float(p)