The pattern "[ $? -ne 0 ] && util::err ..." is problematic since it
leaves an exit status of 1 if the test fails, which is the non-error
case. So various commands (e.g., vm datastore add) return status 1 even
when they succeed if this pattern appears as the last line of a command
implementation.
Fix this by mechanically converting this pattern to
"[ $? -eq 0 ] || util:err ...".
If you have a directory (or network mount) containing iso files, you
can configure vm-bhyve to look there by adding it as
a media datastore. (vm datastore iso my-media /path/to/iso/dir).
Also we now look in the current dir for iso files, and accept full paths.
I already do pretty much everything they advise anyway
Grouping functions together by using "prefix::" is quite a nice feature though.
Nothing too clever, just makes use of the fact that a colon appears
to be a valid character in a shell function.
Create functions to load and get values from this independently
Don't need to resort to sysrc for switch/datastore now due to worry
of loading their config over the top of current guest
