merging directories

Start directory comparison using ztree-diff command. Once you find
the file with changes you can hit enter and go to ediff mode.

1. Ztree-diff commands

Key binding	Command
n	next difference
p	previous difference
a	Copy changes from buffer a to b
b	Copy changes from buffer b to a
wa	Write buffer a changes to file
wb	Write buffer b changes to file
?	Toggle help