Return datetimes without needing call to cdfepoch.to_datetime

[johncoxon]

I don't know how difficult this would be, but one improvement I'd like to see cdflib implement is have sensible datetime objects returned by cdf files, rather than needing a call to cdfepoch.to_datetime. For instance, consider the following two examples, one from cdflib and the other from pycdf:

cdf = cdflib.cdfread.CDF("/path/to/file.cdf")
time_array = cdflib.cdfepoch.to_datetime(cdf.varget("Epoch"))

cdf = pycdf.CDF("path/to/file.cdf")
time_array = cdf["Epoch"][:]

It would be really nice to be able to expect cdf.varget("Epoch") to return useful datatypes by default, rather than having to have an intermediate step.