Add Query Editor within UDDL Editor support

[steve-hickman-epistimis]

UDDL Queries are completely embedded in strings in Conceptual/Logical/Platform Views. They have their own syntax. To ensure they are well formed, we really want the Query editor to be used when editing this string.

It may be possible to learn how to do this by looking at how Sirius and XText are integrated:
See

• https://altran-mde.github.io/xtext-sirius-integration.io/userguide/
• https://github.com/altran-mde/xtext-sirius-integration/
• https://blogs.itemis.com/en/domain-specific-visualization-of-textual-models-with-xtext-and-sirius