Add nested events feature test.
Grammar update for nested events.
Solve filter choice conflict.
Typo
BDPL nested events syntax update.
Add simple test to check syntax tree.
 Make simple syntax test more specific. (Check operators)
Add nested events tree test.
Update nonterminal names.
Unit tests updates.
Clean up.
Fix missing variable bug.
Add filter direct to ElementEventGraph.
Fix query.
Query class update and new collection tests.
Test updates.
Add debug message if no historic part exists to collect stream id from.
Clean up.
Quote binary operators.
Fix stream id.