Install Scripts: Documentation updates, fix group permissions

Add note concerning how to connect using SFTP and the user required to
do so.

Change prompt to new default of "OSEHRA>". Add note that it is based on
$instance

Fix group permissions by adding a chown command at the end of
autoInstaller.sh

OSEHRA-Id: http://issues.osehra.org/browse/VAF-166
OSEHRA-Id: http://issues.osehra.org/browse/VAF-165
Change-Id: I1b8e45fc24db436fb5bec9e6d4e87e1300c62101