applied Matlab compatibilies with Octave

Various changes which make the M-Files compatible
with both Matlab and Octave have been applied.
Octave is surprising compatible.  Only once case,
converting a z-domain transfor to state space,
hasn't been resolved.

- removed 'endfunction'
- removed 'endfor', replaced with 'end'
- Matlab does not support default function arguments,
  used 'narg' instead.
- Matlab accepts 'InputName' instead of 'inname' and
  'OutputName' instead of 'outname' for the control toolbox.