Fix a number of bugs
Fix a number of bugs

After we find the start of a comment block, advance immediately
 - this is so we do not mistake "{#}" as both open and close of comment
support do/set statements (no {% enddo %}/{% endset %})
fix some edge-case bugs around quoting
fix a bug around materialization parsing

analyst-collective/dbt,fishtown-analytics/dbt,fishtown-analytics/dbt,fishtown-analytics/dbt,analyst-collective/dbt