Fix xsd namespace.
Correct unbound variable
Do not transform strings to number. Ref: #17
Add filter type check test. #17
Little data type check. #17
Update.
Update package name.
Add nested events example.
Clean up.
Pattern update
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.