Update development-notes.md

Bump version number, record testing notes, fix plots in validation suite

Final cleanup to remove unneeded dependencies

Update release name to 0.8

Merge pull request pingswept#87 from efiring/version8

Update setup and docs for 0.8rc2; fix reference_frame.png.

Merge pull request pingswept#60 from ArneBachmann/master

Corrected leap seconds table for 2016 and added entry for 2017. Sorry for the delay, Arne! Thanks for the code.

Set version to 0.7 for PyPI, mark as Python 3 only

Fix up optical mass confusion. Effective aerosol wavelength definitel…

…y not calculated properly.

Merge pull request pingswept#11 from robintw/master

Add Python 3 support. Thanks, Robin!

Increment version to 0.5