2.6.0b2 upgrade ZEER traag

[riking (Kane York)]

@pfaffman

If there were a way to have ./launcher pass SKIP_POST_DEPLOYMENT_MIGRATIONS=1 into things without requiring an edit to the app.yml it’d make things less fiddly for the editor-challenged.

Good idea, I went and implemented that:

FEATURE: Add easy mechanism for skipping post-deployment migrations