DolphinWX: Mild readability clean up of CodeView.

- Gets rid of the underscore in some function names
- Appends the 'm_' prefix to class member variables.

Now it isn't a pain to see what is being modified in terms of state. Especially in the OnPaint call.
Merge pull request #632 from lioncash/dolwx

DolphinWX: Mild readability clean up of CodeView.