Fix \phi and \varphi

please refer to the last paragraph of the following section:
http://en.wikipedia.org/wiki/Phi#Computing

The python 3 version's default font doesn't support many boldface,
italic and blackboard boldface characters.

Reversing is needed so subseteq appears before subset. This way
\subseteq will translate to '⊆' instead of to '⊂eq'.

Conflicts:
	gui.py