The pre-wrap is unprefixed since Firefox 3.0. The prefixed version is not supported in the current version of Firefox, so the console makes the page very wide.
Bug: T157947
Change-Id: I2a56e5b8f97deb35e5f2fed0d4083ffa7df11833
* Added a debug console to the edit page, allowing unsaved modules to be
tested.
* Removed the "preview" button from the edit page.
* Only show the "ignore code errors" checkbox on module edit pages, not
all edit pages.
* Added Lua function mw.log() for sending messages to the debug log.
Change-Id: Ia51f439e573a1deb5b83f94ddd1a86792d5569c1