Clean up and Improvements

Fixed up a few things and added new toolbars.
Merge branch 'master' of https://github.com/RobertBColton/OpenStudio
Update README.md

typo
Improvements

Implemented a preferences dialog that lets you set one of the Qt
included styles and also fixed the acceptable formats for open and save.
Merge branch 'master' of https://github.com/RobertBColton/OpenStudio
Merge pull request #3 from RobertBColton/master

Improvements