Bug 48190: Avoid flash of unstyled content on diff view

Move modules to top of page
simplify dependencies for diff view and add to top of page
update test code to switch order of jQuery and mw.mobileFrontend
for consistency

Change-Id: I6c0e3d6d331934a7460cc4efcd5513a3652ce7d4
Merge "Bug 48190: Avoid flash of unstyled content on diff view"