Extract by line method
Write user-facing interface to extract all data for a given (list of) IVAR(s), aka a "line" in an actual ICARTT file. So far, you can get all data for a single var (ict.data[]), but this is quite inflexible and not intuitive. Ideally something like:
ict.data[(one or several ivar values)][(names of dvars or ":")]
which would give
np.array( [ (ivarvalue1, ivarvalue2, ...), (dvar1value1, dvar1value2, ...), (dvar2value1, dvar2value2, ...), ...], dtype=[...] )