DRILL-6974: SET option command modification
- ALTER ... RESET ... and ALTER ... SET ... sub-parsers separated to 2
different SqlCall classes with same parent SqlSetOption
- parserImpls modified to handle new syntax of ALTER... SET...
expresion:
a) ALTER ... SET option.name - option.value - setting option value
b) ALTER ... SET option.name - display option value
- Handler for SqlSetOption separated to SetOptionHandler and
ResetOptionhandler for better representation of handled statements
- Base abstract class AbstractSqlSetHandler created to not repeat
shared implementation of same functions
- SetOptionHandler covered with unit tests for each statement
form.
Fix issues stated in the review
closes #1763
