Improve Grep command and add full screen Help command.
Improve Grep command and add full screen Help command.

This change makes Grep silent when a broken symlink is found as well as
open the quickfix window at height of 15 immediately.  Also a new
command Help is added to open the help menu in a full window versus a
split.

jshort/script_party,jshort/script_party,jshort/script_party