GitLab

* Add serialization of reference dataset

* lint and missing file

* Fixes from reviewers

* responded to comments

* revert sdk change

* fix dataset binary file alignment

* many fixes

* fix warnings

* fix bug

* Update file_io.cpp

* Update file_io.cpp

* simplify code

* Apply suggestions from code review

* general

* remove unneeded alignment

* Update file_io.h

* int32 to byte8 alignment

* Apply suggestions from code review

* Apply suggestions from code review

* added all necessary includes - fixed build/include_what_you_use error

* fixed the order of includes (build/include_order)

* fix include

* reduce dependency on header file

* fix build

* Read and write datsets from hdfs.
* Only enabled when cmake is run with -DUSE_HDFS:BOOL=TRUE
* Introduces VirtualFile(Reader|Writer) to asbtract VFS differences