Prove with a unit-test that min() and max() do not work for date.
Introduced a aggregate() function in the DAOFactory so code can be shared.

Also made rawSelect's data-types options more extensible and implemented
the "DATE" case.
Add a test for max(String) and min(String) and support BIGINT as well.
Define the 'DECIMAL' data-type similar to how a FLOAT is defined.

This gives us the possibility to use "instanceof DECIMAL" when needed.
Also handle DECIMAL (similar to the way FLOATs are handled).

This should fix min() and max() for postgres.
Fixed 'type' property of DECIMAL.

This fixed query generation (before the column type was always DECIMAL,
even if DECIMAL(10,3) was specified).
Fixed parsing non-standard DECIMAL during min() and max().

DECIMAL() and DECIMAL(10,3) are not the same - but the type matches.
Handle more data-types in min() and max() that take optional arguments.
Merge pull request #1200 from xdarklight/master

Improved supported data-types in min() and max()