Filter out metadata annotation in word sequences query

[thomaskrause]

Is your feature request related to a problem? Please describe.
In the word sequence query builder, you can add new linguistic sequence from a list of annotations. This list includes all annotations, including the ones attached to meta data nodes.

Describe the solution you'd like
These nodes should not be included.

Describe alternatives you've considered
There is alrready a meta data segment in the query builder, that can be used when #731 is fixed.