README: Update links and text

This hadn't been touched since 2015-12-02, and was getting pretty
stale ;).

Signed-off-by: W. Trevor King <[email protected]>

Author: wking

README.md

@@ -1,14 +1,14 @@
 # OCI command-line API
 
-The [OCI Specifications][specs] currently focus on the bundle-author ↔ runtime interface, but there is renewed interest in specifying a command-line API for the runtime-caller ↔ runtime interface.
-A common command-line API would make it easier to build higher-level tools that are runtime-agnostic (e.g. conformance testers like [ocitools][ocitools-test]).
+The [OCI Runtime Specification][specs] currently focuses on the bundle-author ↔ runtime interface, but there is renewed interest in specifying a command-line API for the runtime-caller ↔ runtime interface.
+A common command-line API would make it easier to build higher-level tools that are runtime-agnostic (e.g. compliance testers like [runtime-tools][runtime-tools]).
 This repository contains initial work on that API, with more detailed discussion in [this thread][thread].
 The usual [development rules][rules] apply, and the legal stuff is spelled out [here](CONTRIBUTING.md).
-The target for the inital design will be to match [the lifecycle pull request][lifecycle], keeping as much similarity with the existing [runC][] command-line as possible.
+The target for the inital design will be to match [the specified lifecycle][lifecycle], keeping as much similarity with the existing [runC][] command-line as possible.
 
-[specs]: https://github.com/opencontainers/specs
-[ocitools-test]: https://github.com/mrunalp/ocitools#testing-oci-runtimes
+[runtime-spec]: https://github.com/opencontainers/runtime-spec
+[runtime-tools-validate]: https://github.com/opencontainers/runtime-tools
 [thread]: https://groups.google.com/a/opencontainers.org/forum/#!topic/dev/BIxya5eSNLo
-[rules]: https://github.com/opencontainers/specs#contributing
-[lifecycle]: https://github.com/opencontainers/specs/pull/231
+[rules]: https://github.com/opencontainers/runtime-spec#contributing
+[lifecycle]: https://github.com/opencontainers/runtime-spec/blob/master/runtime.md#lifecycle
 [runC]: https://github.com/opencontainers/runc