[imp] Hide inactive options

[G G Papazoglou]

Hi. A simple issue here: I disabled some of IMP's options, and they
disappeared from the Options page, as expected (eg. Language or Time
Zone). The only one which
does not disappear is the one regarding Addressbooks, resulting for
the user to be able to click on it, but then see a page with no
options to set. I thought that when an option's sub-options are all
disabled and locked then it should be removed from Options page. This also
happens on the CVS version. Please forgive me if I am missing
something here for such a simple issue... Any help?