DRILL-5419: Calculate return string length for literals & some string functions
1. Revisited calculation logic for string literals and some string functions
(cast, upper, lower, initcap, reverse, concat, concat operator, rpad, lpad, case statement,
coalesce, first_value, last_value, lag, lead).
Synchronized return type length calculation logic between limit 0 and regular queries.
2. Deprecated width and changed it to precision for string types in MajorType.
3. Revisited FunctionScope and splitted it into FunctionScope and ReturnType.
FunctionScope will indicate only function usage in term of number of in / out rows, (n -> 1, 1 -> 1, 1->n).
New annotation in UDFs ReturnType will indicate which return type strategy should be used.
4. Changed MAX_VARCHAR_LENGTH from 65536 to 65535.
5. Updated calculation of precision and display size for INTERVALYEAR & INTERVALDAY.
6. Refactored part of function code-gen logic (ValueReference, WorkspaceReference, FunctionAttributes, DrillFuncHolder).
This closes #819
