LV2 Plugin requires enumeration configurations

The LV2 plugin version of Pianoteq has a turtle configuration file that does not include any enumerations, e.g. the "Output Mode" parameter should allow enumeration of the 4 permissible values but instead allows selection of any floating point number between 0 - 1. Additional configuration within this section for Pianoteq 7 may look like:

lv2:scalePoint [ rdf:value 0; rdfs:label "Stereophonc" ];
lv2:scalePoint [ rdf:value 0.3334; rdfs:label "Monophonic" ];
lv2:scalePoint [ rdf:value 0.6667; rdfs:label "Sound Recording" ];
lv2:scalePoint [ rdf:value 1; rdfs:label "Binaural" ];

with the additional prefix declaration:

@prefix rdf:  <http://www.w3.org/1999/02/22-rdf-syntax-ns#>.

There may be other enumerations that would benefit from this modification.