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ARROW-474: [Java] Add initial version of streaming serialized format.

This patch proposes a serialized container format for streaming producer and
consumers. The goal is to allow readers and writers to produce/consume arrow
data without requiring intermediate buffering.

This is similar to the File format but reorganizes the pieces. In particular:
  - No magic header. It's likely a reader connects to a 'random' stream to read it.
  - Move footer to header. This includes similar information, including the schema.
  - ArrowRecordBatches follow one by one. Each is prefixed with an i32 length. The
    serialization is identical as the File version.
  - See Stream.fbs for more details.

This patch also implements the Java reader/writer.

Author: Nong Li <nong@cerebrodata.com>

Closes #288 from nongli/streaming and squashes the following commits:

554cc18 [Nong Li] Redo serialization format.
03bee58 [Nong Li] Updates from wes' comments.
7257031 [Nong Li] ARROW-474: [Java] Add initial version of streaming serialized format.