add support for vacation-seconds extension
update existing lang files
use lib file structure like the core
some code clean up
allow all drop down lists to be overridden
add some comments
more comments + code clean up
remove duplicated code for rule list generatoin
a bit more code cleanup
slightly reduce number of vars POSTed
fix typo
fix some small bugs
disable unused form fields before sumbit, reduce POST more
update package.xml
update changelog
remove debug code
more CS cleanup
Merge branch 'devel-v2'

Conflicts:
	sieverules.php
fix ajax list building
tiny CS change