Adding support for the IMR consistency test of GR

To-do:

• Add Documentation for loading in TGR specific metafile
• Add Documentation for imrct_kwargs and make it a non-required option.

Done:

• Add Downloads information.
• Fix problems with plt.tight_layout.
• Comparison Pages of IMRCT results and combined constraints.
• Add approximant, and quote inspiral and post-inspiral cutoff frequencies separately.
• Documentation: Add somewhere that code was taken from existing implementation in lalsuite, Document that vectorize will use up a lot of memory
• Remove changes introduced in _version_helper.py
• links to the summary pages for the inspiral and post-inspiral runs
• The fcut values and information about waveforms and final state fits are also missing
• Add option to generate PE Summary Pages if they aren't generated.
• The "About" page I can't scroll to see the portion of the command line that extends off to the right (I don't even see it if I enlarge my browser window) and the "Export to bash" button doesn't do anything.
• making the axis labels larger and fixing the tick label collisions, put a little space between 1d and the 2d plot
• Add plus as the GR value
• use of the non-evolved final state results is currently hard-coded

To Discuss:

• Combined Constraints.
• Add tests.
• "Time (seconds)": not sure if it's a good idea to have it on the main page along with physics results and settings.
• In the way "option to generate PE Summary Pages" is implemented right now, it does not print logger statements to stdout. This is because the summarypages job is launched as a subprocess, and hence the logs would be confusing if both summarytgr and summarypages logs are being printed. The alternative is to launch the summarypages jobs only after summarytgr is done, which would mean that if you are waiting half an hour (say) for the summarytgr job, you will then have to wait even longer for the PE pages to be built.