SCHEMA-198. KijiColumnName validates family names using KijiNameValidator.

TestKijiColumnName contains updated unit tests. KijiInvalidNameException
is now unchecked, satisfying SCHEMA-209. Unqualified names have
qualifiers normalized to null. Group type qualifiers and map type
qualifiers are not distinguished. Byte array get methods for family name
and qualifier now maintain safety of internal state by not caching
(sacrificing some performance).

Signed-off-by: Christophe Taton <taton@wibidata.com>