annotations: addressing comments
annotations: addressing comments

From: https://github.com/opencontainers/image-spec/issues/658#issuecomment-301494825

* Source is not just to binaries.
* the strings already say URL, so it's redundant
* git:// is a valid URL as well
* version MAY be semantic
* 'name' -> 'title'

Signed-off-by: Vincent Batts <d01a4772f0cffd3f005a7d7f01c59cd104c7a5fe@hashbangbash.com>

jonboulle/image-spec,opencontainers/image-spec,jonboulle/image-spec,opencontainers/image-spec