Builds flatbuffers and provides the path to the built flatc. Intended for use
by build scripts, but can be useful otherwise if the project is using flatc during runtime. The flatbuffers version is
determined by the build identifier for the crate version. v0.2.0+2.0.0 means the crate is version 0.2.0 and the
vendored flatbuffers version is 2.0.0. There's no pressure in releasing crate version 1.0.0 since this is primarily
a build tool, so it will come eventually after nothing needs to be fixed/added for a while.
