Disable pretty italics inside links. Now the italics inside a link alternate text will be handled on its own scope but if they come from the page title, they won't be parsed at all. This is a middle way solution to bug 4598. Now all bug 4598 tests pass.
Pretty italics mean that italics go across links: ''Some [[Link|pretty ''italics'' and stuff]]! -> ''Some [[Link|pretty ''italics'' and stuff]]! -> <i>Some <a>pretty <i>italics</i> and stuff</a>!</i>
This also fixes bug 24093, where interface messages saying '''[[$1]]''' has been deleted/renamed/links here were being bitten by this feature.
The best resolution would be to make pretty italics still work inside alternates, feel free to do so, but doesn't seem worth at this point. The right solution should be to rewrite the quotes handling so it takes its scope into account.