Reworking of NSEvent

[Fred Kiefer]

I just changed all the event type codes to different values in SVN. This
change requires that you recompile all you GNUstep libraries and
applications that have an explicit reference to an NSEvent type. You
also need to adjust any code that expects these values to be in a
certain order, as this has changed as well.
This step was necessary to have values that are binary compatible to
Cocoa. I hope to make the porting of applications from OSX to GNUstep a
little less painful by this.

Those of you who work from released GNUstep code will only be affected
the next time you switch to a new GNUstep release.

Sorry for any inconvenience,
Fred