Move ParsedColInfo out of ParsedSelectStmt

I'll be needing this class to handle ORDER BY clauses in DELETE
statements.
Refactor ParsedColInfo to be more statement-type-independent

This is in preparation for allowing ORDER BY clauses on DELETE
statements.
Port Xin's changes from pull request #1891 to new location for ParsedColInfo
Merge branch 'master' into ENG-7132-refactor-parsedcolinfo

Conflicts:
	src/frontend/org/voltdb/planner/ParsedSelectStmt.java
Merge pull request #1885 from VoltDB/ENG-7132-refactor-parsedcolinfo

Refactor ParsedColInfo to be more statement-neutral