Fix typos in documentation

[mhearne-usgs]

There are some typos in the getcsv documentation page:
https://github.com/usgs/libcomcat/blob/master/docs/cli.md#getcsv
In the Optional Arguments table, the --endtime should be --end-time.
In addition, --get-moment-components requires an argument
in that table (all, none, or preferred), and some of the example
below the table have that argument missing. I believe that
--get-focal-angles is similarly missing required arguments.
It might be worth running all of the examples, via copy/paste,
in getcsv or the other command-line tools to see if there are
any syntax errors on that page.