[Bf-taskforce25] RNA groups proposal, implementation stage 3

[Vekoon]

Hi everyone,
A couple of days ago I came back home and yesterday+today I started 
working again on my proposal on RNA groups for rna properties grouping.
I implemented some group types and also a basic layout mechanism in 
which groups break into multiple columns or rows depending on available 
space and layout direction (for the joy of horizontal layout enthusiasts).
As always a 5 minute video is better than tons of words I guess, so 
here's a video demo: http://www.vimeo.com/2975505
In the video description there's also a link for more details on the 
status of the implementation. Note that the video is still being 
converted at the time of writing but you can download the original avi 
at the bottom of the page. Sorry for the slow, crappy video but I did it 
fast and full-screen capture slowed down my machine which caused the 
snappy look.