Misc AIR improvements

Regarding the FB import changes: there seems to be a problem with FDBuild, when it compiles Debug projects, it obeys the output path, which is usually bin-debug, but when it's a Release project, it seems to enforce bin. I tried to look for the cause of the problem, but I didn't find anything of interest. If nobody else looks for it, I'll do again when I look into improving this a bit more in some time.

Also, I don't know why this PR includes 42 commits, instead of the 3 really of interest, but I guess it won't affect anything? 
I've never seen a project with multiple application entries, so I don't know if mainApplication would be a better choice, if the current way is, or if it doesn't matter because it could be any of them.