Control editing...finally

[thelusiv]

I haven't got any kind of copy settings to adjacent controls thing yet, but the settings changed in the edit controls menu should now be saved properly, in SVN r1564. So far, the edit controls menus let you edit the following for different types of controls:

• type: Joy Axis - deadzone, gain, exponent
  
• type: Joy Button, Mouse Button, Key - up/down and held/once
  
• type: Mouse Motion - deadzone, gain, exponent

I'm not quite sure if the Mouse Motion settings will have any effect in-game. Actually deadzone and exponent don't make sense on a mouse. I'll have to fix that...

Please test this out for me and give me some ideas on how to make this a little better.

Some thoughts/problems:

• sliders only set a value between 0.0 and 1.0. The min and max values for deadzone, gain and exponent should all be different from that. I'll have to figure out some kind of solution...
  
• The slider should probably display the value that it's being set to in percentage, but the value wouldn't make much sense without having min/max values.
  
• The mouse-over icon for controls in the controlgrab widget has an X over it, which doesn't make much sense anymore since the action is edit, not delete. I'll make a new icon soon, for now it doesn't change when selected.
  
• There should be some way to copy settings to adjacent controls as Joe has said.
  
• It'd be nice to visualize the values as Joe has mentioned, I can probably adapt some code from the joystick calibration widget and make a new widget that does this.

I'm sort of leaning towards putting off fixing the last two points until the next release cycle. They would both probably take a good bit of extra time, and if I get the other stuff finished up, we could do a release very soon...