Merged Org 7.7

[Bastien]

Dear all,

I've just merged Org version 7.7 to Emacs trunk.

Org was not updated since version 7.4 -- this is entirely
my fault, as I took over maintainership of Org after this
release.  But I needed some time to feel confident about
the best way to make this merge happen.

This is a *huge* commit.  I have been extra careful while
adding the proper ChangeLogs.  If you find anything wrong
in the ChangeLog entries, please feel free to fix it.

I will be off until August, 10th.

Thanks,

-- 
 Bastien