fix #656: do not init on_load and on_new

Large files where causing Goto Anything to fail and throw errors
when using Vintageous. Deleting the on_load and on_new event
handlers (which were only doing anything on OSX) seems to fix the
issue. I can't remember exactly why they were added in the first
place, but I think, without them, Vintageous wouldn't automatically enter
normal mode when ST was coming from a windoless state in OSX.

In my brief testing, the change doesn't seem to cause any
regressions.