Api should be versionable

[addshore]

This is one of the biggest issues I have with the current MW and WB apis.

[JeroenDeDauw]

Yeah, this is an important thing to get right for serious third party usage. The approach taken here makes it a lot easier to do versioning then in the WB API:

• No single "one fits all" format, that needs to be modified whenever something new is added
• REST style content negotiation versioning such as GHs is possible
• No technical and consistency restrictions imposed by a wider framework

That said, I do not think implementing versioning is the first thing to start with. Beginning with a explicitly beta/unstable API to create an initial feature set and get feedback is what I have in mind. Then, once people actually care about stability, the switch out of beta-ness can be made, which will involve deciding on a versioning strategy.