positions by reference, not by value in createDataTag fixed
Merge pull request #315 from asobolev/master

in createDataTag: positions by reference, not by value
Merge remote-tracking branch 'upstream/master' into nix-308

Conflicts:
	include/nix/base/IBlock.hpp
	include/nix/base/IDataArray.hpp
	include/nix/hdf5/BlockHDF5.hpp
	include/nix/hdf5/DataTagHDF5.hpp
	include/nix/hdf5/SimpleTagHDF5.hpp
	src/hdf5/BlockHDF5.cpp
	src/hdf5/DataTagHDF5.cpp
	src/hdf5/SimpleTagHDF5.cpp