Multiple Filter Support

[dorisjlee]

Currently when multiple filters are applied it is unclear if an OR or AND is applied. Not enough explanations and information is displayed on the visualization to indicate this. For example, even though clauses are combined via conjunction, in this example, it seems like only one of the filters is being applied.

df.intent = ["Region=New England", "Region=Southeast", "Region=Far West"]
df

More work needs to be done to extend the language for supporting OR.