Version bump

Bump to 0.0.10.
Overhaul option parsing

Split out option validation into a separate validopts() helper
function, and use it to implement option parsing in `clicraft` and
`clicraft cmd`.
Add options to `clicraft restart`

Add a --warn option to `clicraft restart` which broadcasts a
"Server is restarting" message in chat for 15 seconds before
restarting. Also add an example restart script with additional
--if-empty and --if-crashed options, which only restart the server
if nobody's online or if it's down, respectively.
Rewrite `clicraft edit`

Remove the behavior where comments are ignored when checking
whether to install a new action file.

Use example action scripts as templates.

If a file is empty after editing it, delete it.
Add enable and disable actions

Add actions for enabling and disabling example action scripts.
Fix bug in serverprop()

Don't return an error code if the property is defined but empty.
Make `clicraft restart --if-crashed` more robust

Check that server-port is defined in server.properties, and use
server-ip if it's defined.
Fix bug in `clicraft backup`

Properly set the default for BACKUP_TARGETS.
Rearrange the order of clicraft options

Put --help and --version last in all help output and documentation.
Remove extra whitespace in `case` statements
Document new options and behavior

Document `clicraft restart` options, new `clicraft edit` behavior,
and the `clicraft enable` and `clicraft disable` scripts.
Update enable and disable scripts

Add output to `clicraft disable` to mirror `clicraft enable`,
don't create backups of identical files, and use msg() instead of
echo.