Fixes stravalib#168 - updating scopes

Bumping version.

Updating news for release.

Bumping version for twine upload.

Added news for 0.9.3

Bumping version / changelog for 0.9.2 release.

Fixes stravalib#142 - Let DefaultRateLimiter update limits from headers.

Bumping version.

Cleanup README a bit.

Added release notes.