[release] 2020-02-23 - v0.3.0

[stp-ip]

Is this a BUG REPORT or FEATURE REQUEST?: release

caddy v2 specific

• [x] merge v2 support into master

• [x] update docs for caddy v2

• [x] Update changelog

• [x] Change version

  • [x] /VERSION

  • [x] .seed-config.yaml

• [x] Migrate various test/production instances

• [x] tag alpha, beta releases, if necessary

• [x] Fix/document remaining bugs/PRs

• [x] Rinse and repeat

• [x] Update docs

• [x] Create final tag

• [x] Create Github release

• [x] Copy release notes from changelog

• [x] Test build server run (Caddy)