Gwpy

Bug-fix alpha release
- fix classmethods under update_docstrings
- improve unit tests
- add download progress for large NDS fetches (use iterate() instead of fetch())

Bug-fix pre-release
- fixes issue importing TimeSeries with broken `astropy.utils.compat.gzip` import.

Latest pre-release of GWpy. Changes:
- fixed LAL SWIG-wrappings for new upstream code
- improved documentation for filtering and trigger usage
- a small number of python3 improvements

Bug-fix of the 0.1 alpha release series.