Release version 0.2.5

Changed PHP form names to unique values.

Add start() function to boot sequence boot() if set to true. Mounting is
done before plugins are installed so it is skipped initially on server
powerup, so needs to be done manually in boot() function again.

Changed wording "upgrade" to "update" in refernce to different versions.

Added stop command to virtualbox_updateplg() function because package
installations may be involved in the installplg process.