Use 'reread' not 'replot;reread'

Only the former is required, and it should behave a
bit more nicely than the latter for complicated plots.
Include pause in -s output
Make ShellCheck happier
Remove -r (raise) option.

This can be accomplished with $GNUTERM, and the default raising
behavior is exactly what -r accomplishes if supplied.
Remove broken -S option
Add idea TODO