[bug 1388942] Add snowball analyzer in document mapping.
[bug 1388942] Add snowball analyzer in document mapping.

In ESv2 document mapping must include the 'snowball' analyzer to work with
searches that use it. This change brings Wiki Document mappings in part with
Question mappings which already define the analyzer.

mozilla/kitsune,MikkCZ/kitsune,MikkCZ/kitsune,safwanrahman/kitsune,anushbmx/kitsune,safwanrahman/kitsune,mozilla/kitsune,safwanrahman/kitsune,mozilla/kitsune,safwanrahman/kitsune,anushbmx/kitsune,mozilla/kitsune,MikkCZ/kitsune,anushbmx/kitsune,anushbmx/kitsune,MikkCZ/kitsune