Don't exit() on redefined binding mode. (#2638)
Don't exit() on redefined binding mode. (#2638)

Doing a hard exit() is a rather harsh action for something i3 can handle
perfectly fine and is only meant to be a check to make debugging easier
for users in certain situations.
stapelberg/i3,i3/i3,acrisci/i3,avrelaun/i3,avrelaun/i3,i3/i3,i3/i3,stapelberg/i3,acrisci/i3,Airblader/i3-original,avrelaun/i3,stapelberg/i3,acrisci/i3,cornerman/i3,Airblader/i3-original,Airblader/i3,acrisci/i3,cornerman/i3,Airblader/i3,avrelaun/i3,Airblader/i3,stapelberg/i3,Airblader/i3-original,cornerman/i3,cornerman/i3,i3/i3,Airblader/i3-original,acrisci/i3,Airblader/i3-original,Airblader/i3