Interface improvements + Board Settings

Note:
> Added a board settings button to the edit mode, so people know it
exists. haven't tested if non-boardUsers can access it.
> Modified the new object window: now backgrounds (block, postit) share
a colour picker, text (itext/postit) share a colour picker, and text is
optional.
> There were some occasions when my save didn't succeed, so I worked on
adding an async:false save. Then i noticed you changed the timedout
already, so I stopped. Not sure what's causing the issue now.