Italics first attempt

Lots of problems!
Italics partly fixed

URL's no longer cause issues. Still problems with italics in bold, and
bold in italics.
fixed scope markup.heading
Revert "fixed scope markup.heading"

This reverts commit dd3e6226087715d3c124782b4f5366655b60b751.
Revert "Revert "fixed scope markup.heading""

This reverts commit d211b38f289e9f1544cf15bbc8f6a227f05eb5b7.
ups, fixed heading scope in theme as well.
Italics mostly fixed

Are we bothered about the following:
//Here are some points to address://

Italics are not closed in the above example due to :// recognised as an
URL. Solution is to add a space after the colon.

Alternatively, should full URL RegEx recognition be implemented?
Merge branch 'Dev' of https://github.com/hArpanet/DokuWiki_st3 into Dev
Testpage updated for bolditalics tests
Italics - added comment re. url bug

No current plans to fix this 'bug' so just adding a comment for future
reference.