add more and fix office mimetypes, migrate wrong mimetypes

Forward port of https://github.com/owncloud/core/pull/7767, the icons are left out because master already has new ones. @icewind1991 @MorrisJobke please review
@butonic is this section needed ?
I have a case where the UPDATE doesn't work because the target name already exists.
Maybe we can simply remove the section "update wrong mimetypes" and rely solely on the fix below ?

In the future we want to add a repair step to clean up unused mimetypes.