get rid of some reflections

partially addresses #23

the one thing I'm not 100% sure of, is in `seesaw/event.clj` around line 520
there are two classes which have those 2 methods (with same param types)
`java.beans.PropertyChangeSupport` and `java.awt.Component` but by looking at tests it looks like the latter should be the case, they don't seem to share anything in common ie. a base class/interface. They just happen to have the same method names + types.

I didn't touch others which I wasn't sure of, and I stopped checking when I reached `core.clj` (in the list from `lein test`) because got bored since they are not easily solvable.