#1220 Initial Mac support for changing file and folder names. Not fully complete.

git-svn-id: svn://svn.transmissionbt.com/Transmission/trunk@13828 f4695dd4-2c0a-0410-b89c-da849a56a58e
(libT) #1220 'change top folder names' -- when the root file/folder is changed, update tr_info.name too.

git-svn-id: svn://svn.transmissionbt.com/Transmission/trunk@13829 f4695dd4-2c0a-0410-b89c-da849a56a58e
(libT) update the rename callback to include the previous torrent name

git-svn-id: svn://svn.transmissionbt.com/Transmission/trunk@13830 f4695dd4-2c0a-0410-b89c-da849a56a58e
use the new rename function for the torrent, instead of the per-file function; update the interface right away when renaming the torrent

git-svn-id: svn://svn.transmissionbt.com/Transmission/trunk@13831 f4695dd4-2c0a-0410-b89c-da849a56a58e
add the rename option to the main window context menu

git-svn-id: svn://svn.transmissionbt.com/Transmission/trunk@13832 f4695dd4-2c0a-0410-b89c-da849a56a58e