Support binary Hive type in RCFile scheme

The Hive serde serializes the binary type as a Base64 encoded string. I have made the following change to the RCFile scheme to write the byte[] field as a Base64 encoded string.

I also simplified the RCFileTest class to test both reading and writing in a single test. There is no need to have a test for reading the RCFile since creating a TupleEntryIterator object requires reading anyways.  Furthermore, I added several Hive types in the test to ensure that the RCFile scheme works on those types. The types tested are
* int
* bigint
* float
* double
* decimal
* boolean
* binary
* string
* timestamp

There was also a bug where the fields passed to the creation of the RCFile scheme ignored casing, which goes against users' expectations since we expect the fields of each tuple in the cascading job to be what we defined in the creation of the scheme.