More options and style tweaks

- Add option to hide Open file icons
- Add option to hide folder expand buttons
- Subdue folder expand buttons (now small +/-)
- Drop down tab_control menu icon has been updated
- New close button
- When file icons are disabled, a new low profile dirty indicator is
displayed when appropriate
- Update menu version check to be more flexible
- Hide < 3062 workaround if on ST2 or 3062+
- Add new menu options