JDK-8343018 introduced `--with-jls` and `--with-jvms` configure parameters that allow the referenced JLS/JVMS html folder to be included in `docs/specs`.

JDK-8370153 makes this the standard behavior for standard jib profiles, grabbing latest versions of JLS and JVMS from Artifactory.

With these changes, the `@jls` and `@jvms` taglets no longer need to produce external links to `docs.oracle.com`. They can just point to the local `specs/jls` and `specs/jvms` directories. Happily, this means the links should work right away rather than needing to wait until the future publication of the latest JLS/JVMS at `docs.oracle.com`. (And, per JDK-8339558, the URLs can be validated immediately.)