scriptworker 2.0.0

Since my last blog post, we've released seven more 1.0.0bX betas and a 2.0.0 final.

Since then, we've added beetmover-, balrog- and pushapk- scriptworker instance types, with chain of trust support, and upgraded them off of the now-retired 0.7.x branch. We now have a live_backing.log for easier treeherder log viewing. Our configs are now recursively frozen for more immutable goodness, and we have an unfreeze function as well. We're now running scriptworker instances against tier1 linux and android Firefox nightlies (and developer edition). And we have more contributors and contributions, including two releases pushed by jlund and jlorenzo.

Why 2.0.0? First, we introduced some backwards incompatible changes , and decided that the spirit of semver rule 5 included 1.0.0 betas. Why not 2.0.0b1? We're in production, tier 1, so let's stop futzing with betas and call it 2.0.0. The major version should be incrementing fairly rapidly, since we have a number of changes in the pipeline that may be backwards incompatible. Skipping 1.0.0 and getting used to larger major version numbers seems like a good first step.

Thanks Johan and Jordan, Mihai for the beetmover and balrog work, Pankaj Ahuja for the recursive freeze/unfreeze functions, and a bunch of other people on the Releng and Taskcluster teams for all their help!