various fixes + UI improvement

The first commit fixes enet builds on FreeBSD. The files are copied directly from latest Tesseract Git, effectively replacing your own. I left in your gitignore though.

The second commit fixes rpgeffect compilation on gcc 4.2.1, it won't take it without the casts (errors).

The third commit improves the UI in case you ever wanted to add overlapping (and possibly floating) windows - it makes hover and select signals only work on the topmost window in the cursor position if several are overlapping - that makes sure you can't click through a window for example. With the current setup the behavior is unchanged (because you have no overlapping windows) though.