Add and rephrased option comments.
unset CDABLE_VARS since it only works with cd and thus leads to problems
when trying to use the notation with other programs (since it became a
habit)
Set new options.
Add functions comp-conf and comp-source heavily inspired by romkatvs
jit & jit-source.
Replace every call to source with comp-source.
Remove existence check since it is done in comp-source.
Replace still existing readable checks with existence checks.
Add hint if reboot is necessary after updating.
Add alias to grep a date string.
Always scale images opened with feh to fit the window.
Add alias to open a "temporary" shell in alternate mode that does not
mess with the scrollback history.
Switch from gnome-terminal to st (see fork on github).
Open new terminal by default in the same working-dir as current window.
Modify scratchpad-terminal to work with every terminal.
