#289 Set the highest available refresh rate by vidmode

[Deve]

Some people reported that Irrlicht sets the lowest available refresh rate on linux. For example here:
https://github.com/supertuxkart/stk-code/issues/1313

This is probably caused by changes in linux drivers. I remember that in the past refresh rates were displayed from the lowest to the highest (for example on xrandr list). Currently they are display in reversed order.

It is a problem if device supports 20 or 30 Hz output...

This patch checks refresh rates and sets the highest available refresh rate for specified resolution.