New Recording UI

Fix #622

Implemented the layout discussed in the issue as well as some other changes listed below.

- [x] New recording UI layout
- [x] Buttons are now persistent
- [x] All buttons now use only icons
- [x] Custom icons consistent across all platforms (no system icons)
- [x] Record button does not have to remain pressed (Stop button used to look pressed)
- [x] Added "Leave record mode" button
- [x] Output file now gets deleted if never recorded to
- [x] New button style (Record-mode buttons more prominent)
- [x] Moved Auto-Record to Options menu, removed button from Recording UI
- [x] Added Ctrl+R shortcut for auto-record
- [x] Added button to leave auto-record
- [x] Ctrl+R also works in auto-record for leaving

Screenshots:
Windows
![new recording ui](https://cloud.githubusercontent.com/assets/5759678/4585209/f94ef2e6-5002-11e4-9dc3-7ed62119d818.png)
![new recording ui 2](https://cloud.githubusercontent.com/assets/5759678/4585210/fb95dd26-5002-11e4-875d-b59d435550ca.png)

Linux
![new recording ui linux](https://cloud.githubusercontent.com/assets/5759678/4585238/3d08b8aa-5003-11e4-9d85-fc5b56aa9de3.png)
![new recording ui linux 2](https://cloud.githubusercontent.com/assets/5759678/4585239/3d2a7350-5003-11e4-928e-1c83583b81f9.png)


There's an opportunity to use the tooltip to give the user additional information about what the button does or why it needs to be pressed, rather than having it repeat the same button text which adds no value.