schema/schema.json: Update main description

The README title is:

    Open Container Runtime Specification

And the config.md title is:

    Container Configuration file

The JSON Schema covering that configuration file should have a
description that combines those two titles without introducing new
language.

Signed-off-by: W. Trevor King <wking@tremily.us>

schema/schema.json

@@ -1,5 +1,5 @@
 {
-    "description": "Schema for OpenContainer bundle configuration file",
+    "description": "Open Container Runtime Specification Container Configuration Schema",
     "$schema": "http://json-schema.org/draft-04/schema#",
     "id": "https://opencontainers.org/schema/bundle",
     "type": "object",