Removed call to self.get_n_dim_form()
Fixed bug in loop over labels and sizes
Fixed bug when only a single position selected.

Bug if h5_pos is array of size 1.

Removed some unneeded lines of code and slight docstring change

Added exceptions to getH5DsetRefs and findDataset to allow returning of normal H5 Dataset if not a 'main' dataset

Function calls that used to return h5py.Dataset objects will now return PycroDataset objects.

Refactor how dataset attributes are set.
Added more documentation for the class.

slice method now operates directly on the h5 dataset.
Added some documentation

Fixed errors with labeling due to not having datasets for Position and/or Spectroscopic dimensions