Small GUI modifications:

- Removed dialogs that required user input during the middle of the simulation run. These warnings have been moved to the status bar at the bottom
- Added checkbox that triggers whether the sensitivity analysis is performed
- Added a user input box that allows the user to change the sensitivity analysis value
Introduction of the sensitivity analysis results window w/ two adjustable panels
Major GUI changes:

* Updated the GUI library which brought many bug fixes and updates to the graphic objects used
* Introduced a checklist for input variables in the SA window. The checkboxes are currently not maped
* Introduced a rough version of the SA output.
Merge pull request #19 from sharrington93/master

Major GUI Update Package