Making filter block compliant with new enum model
BLK-33 Updates dynamic fields block to use expression property

Signed-off-by: Oren Leiman <oren@neutral.io>
BLK-33 Updates Filter block and tests to use ExpressionProperty

Signed-off-by: Oren Leiman <oren@neutral.io>
fixes default value of select property
remove default True from condition expr
Merge pull request #3 from nio-blocks/enum_compliance

Enum compliance