fix#1836
AvatarSelector is mostly copied from AttachmentTypeSelector. I first started to make it a subclass, but there were so many functions that had to be changed that I decided against it (esp. also the constructor, so I would have had to create another constructor to allow AvatarSelector to bypass the "normal" constructor). Could still be done though, of course.
I think (hope joy) that the commits are clear enough that this can be reviewed commit-by-commit. In the first commit, commenting out code means "Moved somewhere else"
I found it easier to look at the first commit using gitk than GitHub as GitHub doesn't show it as copied from AttachmentTypeSelector but as a new file. (of course you can also just review normally, going throug it file-by-file :)
* Don't show remove button if there is no image yet
* Remove unnecessary animation that just made things look worse
* Delete now-unused ClearProfileAvatarActivity
* For groups, also use the attachment-chooser-dialog
* Remove confirmation dialog for removing avatar (The user has to confirm anyway, and this was not correctly translated)
adbenitez