GDS usability: operation without a mouse

GDS usability: operation without a mouse

Derek Peschel provided this patch and described it as follows.

"Most of the time I use Terminal in OS X, rather than xterm.  I also don't
bother with the GUI versions of Emacs.  So unfortunately I have no mouse
support in Emacs.  Also the system I'm testing Guile on thinks my terminal
doesn't support color and I haven't fixed it yet.  The attached patch makes
GDS more usable for me.

"With no mouse, the "[click here to show error stack]" design is very
inconvenient.  You added a C-M (return) binding at some point.  I copied
that, but I also changed the message to show it.  And I made the return
work when the cursor is after the right bracket."

* emacs/gds-scheme.el (gds-display-results): Make "click here" message
  more helpful for people without mice.  Also extend text properties
  so that a RET key press works at the end of that line.