#139 Rename fixups do not include wiki:// links

[Royston Shufflebotham]

Fixups during topic renames miss out WikiNames
embedded inside wiki:// links:
the "Formatter.extractWikiNames" regex is too
restrictive.

Repro:

1. Ensure PlayPage5 exists
2. Ensure PlayPage6 exists
3. Reference wiki://PlayPage5/ in PlayPage6
4. Observe a link in PlayPage6 to PlayPage5
5. Rename PlayPage5 to a new unused name, applying
fixups.
6. Observe the link in PlayPage6 still refers to
PlayPage5.

[scalder]

Logged In: YES
user_id=1448853

NB. Rename fixups also do not include Relabelled links, of
the format:

"SomePage":Namespace.WikiLink