Update numpy version on travis
Remove all image reduction functionality

Closes #173
Make astropysics a test-only dependency

Note that you do need install astrophysics for full functionality. scipy is required by astropy, so it is also listed as a test dependency.
Use the astropy sphinx extensions from astropy-helpers
Remove reduction docs

The underlying code was removed...
Ignore .eggs folder
Remove _static from sphinx configuration

It is not being used and generates a warning
Add summary as alias for summary_info

Closes #175
Use overwrite instead of clobber in iterator arguments

Closes #174
Add __all__ to table_tree
Update installation instructions to reflect new astrophysics status
Update docs
Reorganize docs to emphasize image collections

Closes #171