* extend filter checking
* extend IResearchViewNode tests
* distinguish scorer and filter arangosearch functions
* initial implementation
* add some tests for the recently added aql functions
* more tests
* force phrase function to use context-wise analyzer
* more tests
* ensure exists function uses analyzer from context
* fix query execution tests
* allow to override context analyzer in phrase function
* modify EXISTS signature to accept optional analyzer, fix tests
* more tests
* even moar tests
* more tests
* update documentation
* add testing scorer
* fixes after review
* attempt to fix msvc compilation issues
* add extra check
* add another check