Nuke incorrect usage of .Ar; replace it with .Vt, .Va or .Fa appropriately.
The .Ar mdoc(7) specifier should only be used when displaying command line
arguments.
Approved by: des (mentor)
Capitalize the first letter of the descriptions for the entries in the ERRORS
section if they are complete sentences and end the sentences with periods.
incomplete and some are just placeholders but I wanted to try to get
something at least into 2.2 on the grounds that what I have is a lot
better than nothing. I also wanted to commit something which documents
the interfaces in 2.2 before I start updating the documentation for 3.0.
This is a definite 2.2 candidate and is also relavent to 2.1 if people
still care about that branch.
