Adds synopses for those commands missing them.
Moves all synopsis sections to code blocks. This improves the appearance, although highlighting as
fish code may not be the ideal appearance.
This adds a new mechanism for logging, intended to replace debug().
The entry points are FLOG and FLOGF. FLOG can be used to log a sequence of
arguments, FLOGF is for printf-style formatted strings.
Each call to FLOG and FLOGF requires a category. If logging for a category
is not enabled, there is no effect (and arguments are not evaluated).
Categories may be enabled on the command line via the -d option.
This adds an option --print-rusage-self to the fish executable. When set,
this option prints some getrusage stats to the console in a human-readable
way. This will be used by upcoming benchmarking support.
