prepare for 0.3.15 release.

fix a flaky test under 3.7.

hopefully.

bump for 0.3.13

bump to 0.3.12 release.

Update changelist, bump to 0.3.11

Bump version to 0.3.10

bump version to 0.3.9

bump version to 0.3.8

bump version to 0.3.7.

bump version to 0.3.6