Decoration revision labels to a web-view (initial implementation)

WebStatus gets new parameter named shortrev in order to decorate
revision labels. It works in same way as revlink decoration but also
supports int type.

Int value stands for max revision label length.

None value is a shortcut for shortrev=12 just to show revision labels in
old fashion.

Tested on v0.8.7p1 (in production) and rebased  on top of master