Fix reading mzML instrument

[Mailaender]

I accidentally hardcoded it to only read

[Term]
id: MS:1000554
name: LCQ Deca
def: "ThermoFinnigan LCQ Deca." [PSI:MS]
is_a: MS:1000125 ! Thermo Finnigan instrument model

because I misunderstood the ontology. Also @ProteoWizard does this

<referenceableParamGroupList count="1">
  <referenceableParamGroup id="CommonInstrumentParams">
    <cvParam cvRef="MS" accession="MS:1000556" name="LTQ Orbitrap XL" value=""/>
    <cvParam cvRef="MS" accession="MS:1000529" name="instrument serial number" value=""/>
  </referenceableParamGroup>
</referenceableParamGroupList>

which is now also understood.