Updated launchctl load options for Mountain Lion

I noticed after installing the dnsmasq formula, the described manner of loading the service via launchctl wasn't working.  I would simply get a "nothing found to load" message.

Consulting the launchctl man page on Mountain Lion reveals the following option:

-w       Overrides the Disabled key and sets it to false. In previous versions, this
                       option would modify the configuration file. Now the state of the Disabled
                       key is stored elsewhere on-disk.

So this patch adds the -w -F options to the load command in caveats.rb (-F forces the service to load even if it's set to Disabled in /var/db/launchd.db/com.apple.launchd/overrides.plist)