not all types are written correctly or even written

[doutriaux1]

Test/test_numpy_nc4.py

types failing for sure:

numpy.int, numpy.uint8, numpy.ubyte, etc...

[doutriaux1]

some test might be OS dpeendent int64 for example fails on my ubunutu because it has been saved as int32

[doutriaux1]

AssertionError: dtype('uint32') != <type 'numpy.uint64'>