Added new icons, taken from the following sources:

https://www.iconfinder.com/iconsets/font-awesome
https://www.iconfinder.com/iconsets/world-issues
http://www.clker.com/clipart-127614.html
Improved the display of the flow menu.
Added an icon for the main gesture menu.
Added a new icon for explosives, detonating explosives and placing explosives.
Added a new medical icon from https://www.iconfinder.com/icons/81006/caduceus_icon#size=64
Merge branch 'master' into NewIcons