plugin interface: introduce templated loop/loop1 functions

loop/loop1 have the same semantics as the LOOP/LOOP1 macros, except they
are inline functions, making the code more friendly for a debugger

Signed-off-by: Tim Blechmann <tim@klingt.org>
scide: remove ctrl-b shortcut

in most cases one can use `ctrl-shift-b` to reboot the server. not sure
if we need a shortcut for boot-or-quit

fixes #699

Signed-off-by: Tim Blechmann <tim@klingt.org>