[Vala] more posix for 0.7.3 release

["Michael 'Mickey' Lauer" <mickey vanille-media de>]

Hi guys,

thanks for applying all the posix enhancements, I could reduce my diff a lot :)

Here's some more which you might want to review, on top of master: 

http://git.freesmartphone.org/?p=vala-
lang.git;a=shortlog;h=refs/heads/mickey/0.7/posix

Cheers,

Mickey.