Allows you to add, and test for the presence of a magic 4-char
string in a FlatBuffer.

Tested: on OS X.

Change-Id: I090692a9e4fb53bed3543279a28563e67132cba0

Implement code generation and runtime library for Go, derived from the
Java implementation. Additionally, the test suite verifies:

 - the exact bytes in the Builder buffer during object construction,
 - vtable deduplication, and
 - table construction, via a fuzzer derived from the C++ implementation.

Change-Id: Ib95a019c684891def2b50281e570b4843fea7baa

Change-Id: I4c9f0f722490b374257adb3fec63e44ae93da920
Tested: using VS2010 / Xcode / gcc on Linux.