DRILL-363: Custom null handling in hash functions
Added custom null handling for hash functions, to override the privies NULL_IF_NULL handling. Added Integer and Float literals to the logical expression package and corresponding methods in the various visitor implementations. Also added new Hash functions for double and float values based on the doubleToLongBits and floatToIntBits methods in the corresponding boxed primitive classes together with the previously used murmur3_128 hash algorithm used for plain Ints and Longs.
Signed-off-by: Jacques Nadeau <jacques@apache.org>
