Add the coverage command to the CLI.

Progress on #1118.

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MOS_MIGRATED_REVID=140128848
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/BuiltinCommandModule.java b/src/main/java/com/google/devtools/build/lib/runtime/BuiltinCommandModule.java
index 506f7ff..672ae34 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/BuiltinCommandModule.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/BuiltinCommandModule.java
@@ -16,6 +16,7 @@
 import com.google.devtools.build.lib.runtime.commands.BuildCommand;
 import com.google.devtools.build.lib.runtime.commands.CanonicalizeCommand;
 import com.google.devtools.build.lib.runtime.commands.CleanCommand;
+import com.google.devtools.build.lib.runtime.commands.CoverageCommand;
 import com.google.devtools.build.lib.runtime.commands.DumpCommand;
 import com.google.devtools.build.lib.runtime.commands.HelpCommand;
 import com.google.devtools.build.lib.runtime.commands.InfoCommand;
@@ -38,6 +39,7 @@
         new BuildCommand(),
         new CanonicalizeCommand(),
         new CleanCommand(),
+        new CoverageCommand(),
         new DumpCommand(),
         new HelpCommand(),
         new InfoCommand(),