Add mediawiki.ui.button to places in core using mw.ui

All of these also use other mw.ui features (e.g. mw-ui-vform,
mw-ui-input, mw-ui-checkbox-label, etc.), so they can't only depend
on mediawiki.ui.button.

Change-Id: I6906533753185f7de42552cff38a86fb0171d1d8
Merge "Add mediawiki.ui.button to places in core using mw.ui"