Use case (website visitor): rotate/reset map bearing

[AmeliaBR]

This issue is for discussion of the use case “Rotate a map, or reset the bearing”, its examples & list of required capabilities.

This is a web-visitor use case: end users may want to rotate the map to make it easier for them to understand, regardless of whether the website author explicitly added this capability.

Related to #84, which is the authoring use case (the ability for the website author to set the bearing of the map, whether to implement a custom rotation control or to set a specific rotation for editorial reasons).

[prushforth]

Should we mention the associated need to provide a bearing for the initial map state, and to reflect the bearing to a map property as it may change?

[prushforth]

OK nevermind, I see that the two are being treated separately.