We don't have a low-latency sub-solar mass search at the moment.
The minimum mass in the mass diagram should be 1, not 0, Msun.

Some email clients such as Exchange do not support subaddressing.
(In other words, they don't support email addresses that contain
a `+`). @thomas.downes set up the email alias
`emfollow-userguide@support.ligo.org` for us.

Change the IVORN prefix from `ivo://gwnet/gcn_sender` to
`ivo://gwnet/LVC`, because GCN traditionally uses the text after
the `/` to indicate the name of the mission, which most closely
corresponds to "LVC", short for "LIGO/Virgo Collaboration".

Note that this IVORN is used for historical purposes and continuity
with the GCN notice format used in O1 and O2, and is likely to
change in the future with the commissioning of additional
gravitational-wave facilities.

Leo Pound Singer authored 6 years ago and Leo Pound Singer committed 6 years ago

The sky map plots take longer to generate than the FITS files
themselves, so they would have needlessly delayed the preliminary
alerts.

Add a plot of the mass categories in m1-m2 space.

For HasRemnant, maybe we could make a
[ternary plot](https://en.wikipedia.org/wiki/Ternary_plot)
in m1-m2-chi space?