Arvados

Open to discussion, but I think it would be good to cover these on the documentation page for each SDK, as well as each SDK's README.

• SDKs we use to build Arvados (Go, Python, Ruby?) are expected to be API-stable. For APIs we expect users to use, we won't intentionally break the API except at a "main" release with notice.
  • It would also be good to spell out what APIs you're expected to use. For example, stuff with a leading underscore and stuff under arvados.commands is not considered user-facing APIs in the Python SDK.
• Other SDKs (Java, R) are not as mature yet. Their APIs may change at any release. (And maybe say, if that's causing you problems, please get in touch and let us know.)