[Unison-hackers] Mac UI improvements

[Ben Willmore]

Here is a patch:
http://socrates.berkeley.edu/~benwill/toolbar.patch

and a .tar.gz containing binary files:
http://socrates.berkeley.edu/~benwill/toolbar.tar.gz

 that make the following improvements to the Mac UI:

* Replace 'Open', 'New' etc buttons with a toolbar for common actions,
based on the GTK one
* Improve validation logic for menu items
* Make sure a tableView row is selected after update
* Enlarge the ConnectingView so the window zooms less often
* Enlarge the PreferencesView to make room for longer entries
* Update the ConnectingView faster when it appears
* Fix bug where status text would write on top of old values
* Use fixed-width font for detailsTextView & increase window size so it fits
* Slightly improve the icon

Most of the toolbar icons are (c) Jasper Hauser, and are under a
license that allows them to be freely redistributed as part of a
software package (e.g. inclusion in SVN is OK), but not inclusion in a
new software package.  Jasper also asks for a mention of his website
(http://www.jasperhauser.nl/icon/) on the Unison website.  See
uimac/LICENSE.icons for details.  If this is problematic, I can
probably make some (less good) icons.

I would be happy if an SVN-enabled person would take a look at them
and commit them if considered worthy.

Cheers,

Ben