require module version

pyparsing 2 is for python3
markdown 2.3 and beyond targets python 2.6 and beyond

So, while tiddlyspace targets 2.5, this is what we've got.
Badly need to change this.
Merge branch 'master' of github.com:TiddlySpace/tiddlyspace
Merge branch 'master' of github.com:TiddlySpace/tiddlyspace

Conflicts:
	setup.py