shortened name in Angle.__repr__
docs trhough angles
fixed __repr__ of Distance
Distances doc section
added custom coordinate system instructions
transformations docs
switched to NumpyRNGContext
fixes for rebasing against current master
Fixed typos in coordinates docs
Added tests for compressed tables
Fixed test name
PEP8
Created a context manager that can understand filenames, URLs, file objects, and can deal on-the-fly with gzip and bzip2 compression.
Fixed order of type checking to avoid TypeError
Follow on to #425.

This integrates `astropy.io.vo` to use the new function.

It fixes the following issues with the new function:

   - Python 3 compatibility

   - Adds a "binary" flag to determine whether the resulting file object should return bytes

   - Doesn't close file descriptors that were passed in
Moved astropy.config.data to astropy.utils.data
Started tidying up code in utils.data
Fix failing tests
Fixed imports
Added back fixed to urllib for context manager