add suggestions for katscript keyword arguments

Fixes: #624 (closed)

Input

import finesse

m = finesse.Model()
m.parse(
    """\
m m1
readout_rf pdh m1.p1.o f=1 output_detector=true
"""
)

develop

finesse.script.compiler.KatDirectiveBuildError: 
line 2: 'readout_rf' got an unexpected keyword argument 'output_detector'
   1: m m1
-->2: readout_rf pdh m1.p1.o f=1 output_detector=true
                                 ^^^^^^^^^^^^^^^
Syntax: readout_rf name optical_node=none f=none phase=0 output_detectors=false pdtype=none

this branch

line 2: 'readout_rf' got an unexpected keyword argument 'output_detector'

Did you mean 'output_detectors'?
   1: m m1
-->2: readout_rf pdh m1.p1.o f=1 output_detector=true
                                 ^^^^^^^^^^^^^^^
Syntax: readout_rf name optical_node=none f=none phase=0 output_detectors=false pdtype=none