* (bug 28627) External link normalization now handles file: URL cases without throwin...

* (bug 28627) External link normalization now handles file: URL cases without throwing notice warnings.

Added some test cases for wfMakeUrlIndex() to GlobalTests (tweaks $wgUrlProtocols to toss in file:// support so it can test them).
Needs more cases for other URL styles probably; some of the more pathological file: URL cases still won't normalize really cleanly but will go through the function without exploding. The most-needed variants will be the Windows/IE-compatible ones I think -- so file:///c:/foo or file://server/foo.