Small improvements, small version change

@ProLoser made window overlay mode more useful, by not reacting on mouseovers even if the "make opaque while I'm working with it" option is enabled: clicks are ignored on overlays, so is mouseover. Pull #2

@tyilo bumped version to 2.4.1 in pull #1. Going back to semantic versioning: github tags will reflect the application visible version number.

Thanks! 😸

MacOS 10.9 Mavericks + EasySIMBL

This is a mostly cargo-culted recompilation of @fjolnir's fork of Afloat, after going through the (rather amazing) automated refactor of Xcode 5.0, that disabled Objective-C GC and converted the code to use Automated Reference Counting.

Technical babble aside, this release works on MacOS 10.9 Mavericks in connection with EasySIMBL. Just download EasySIMBL, install it, then download the attached .ZIP file, decompress it and drag the Afloat.bundle in the EasySIMBL window. Done!