Updated mediawiki/extensions
Project: mediawiki/extensions/Echo  b090b749de40564341d44fbac2a1aa71ebe67373

Messages/Alerts text is tiny in Monobook

Just like all other text elements in the overlay: set the font-size to 13px
Not sure why this was em & rest px. 13px is equivalent to the current 0.8em in
Vector.

Change-Id: I29d67f21cc2af7209469299ab228ebe7dac98af7