Added missing artist results

Searching for missing artists now returns a simple list of artist names,
and a link to view their missing albums.
Ger Translation + Translation Catalog updated. + catalog_update.inc

I sometimes ran into errors if I import all my catalogs, because of the
PHP memory limit. So I decided to add an option for a temporary
deactivated PHP-memory limit. it is default set to off, so there is
enough security for user who read the help^^
I also have added the option to decide if you want a Database Table
optimization or not, because in my case it takes about 5 min to complete
and I wont ever optimize my tables.

last but not least:
I have disconnected the forced gather-art and import playlist from local
catalog add. Sometimes you wanna add songs as fast as possible. Gather
Art has no priority für a funktioning and useful Media library, so it
could be done after it or if the user wants it, it can also be done via
a switch. Like all the others.

So I think I've mentioned all changes I've made^^

EDIT: Updated (7)
EDIT: There isn't a -t (any more)
Merge pull request #626 from Psy-Virus/develop

Ger Translation + Translation Catalog updated. + catalog_update.inc
Temporary workaround to disable sorting on stats related pages (favorites, popular, newest, recent, top rated, wanted list)
Merge branch 'develop' of https://github.com/bliptec/ampache into bliptec-develop
Fix missing artist search result web path
Merge branch 'bliptec-develop' into develop
Add an action to clean expired shared objects (fix #618)
Fixed #632: URL file suffix after transcoding
Update GetID3 to latest master revision to correct merging of multiple genres for ID3v2
Revert "Omit multiple genre processing as it doesn't work in all cases."

This reverts commit 2dfcb06a6d8c5f33a5dbff1acf87e7cd12d7c587.
Merge branch 'upstream_develop' into develop