//   - Names cannot contain whitespace or newlines.
//
//   - Names must be valid unicode, with no unprintable characters.
//
//   - Names may contain at most one ':'. In the counter "foo:bar", we refer to
//     "foo" as the "chart name" and "bar" as the "bucket name".
//
//   - The '/' character should partition counter names into a hierarchy. The
//     root of this hierarchy should identify the logical entity that "owns"