Fix attachment upload link bug caused by introduction of zen mode.
Disable dropzone in ZEN mode
Search for 'div-dropzone' correctly
Merge branch 'fix_selecting_them_upload' of gitlab.com:gitlab-org/gitlab-ce
Merge branch 'fix_selecting_them_upload' into 'master'

Fix selecting them upload

Related to https://gitlab.com/gitlab-org/gitlab-ce/commit/58c0a4f5cf27f76f1dc0474197b8aca06b6db12d#note_293570

See merge request !198
Merge branch 'master' of gitlab.com:gitlab-org/gitlab-ce
Merge branch 'master' of github.com:gitlabhq/gitlabhq