properly preserve the cursor position when going from the "Read File" or

properly preserve the cursor position when going from the "Read File" or
"Save File As" prompt to the file browser to the "Go To Directory"
prompt, and then canceling back to the "Read File" or "Save File As"
prompt

git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@3850 35c25a1d-7b9e-4130-9fde-d3aeb78583b8