Fix reference-counting bugs caught by cpychecker.
Further simplification
Fix a bug when generating the error message in `generate_config_file`.  The stdout and stderr parts are rightly decoded as UTF-8, but then they are formatted into a byte string which (at least on my platform) treats the UTF-8 as ascii and boom! exception is raised trying to generate the error message.
Fix typos
Merge pull request #914 from mdboom/misc/cpychecker

Fix reference-counting bugs caught by cpychecker
Merge pull request #912 from mdboom/setup/generate-config-file-error-message

Fix a bug when generating the error message in `generate_config_file`
Update the changelog with all the 0.2.1 changes that have thus far been merged into the 0.2.x branch.
Merge branch 'master' of github.com:astropy/astropy
Use full package names.