Implement rev-list

This commit introduces the RevisionRange, which more closely follows real git
in terms of identifying a range of revisions than the current implementation of
log. RevisionRange is being used in the new rev-list command first because it
is easy to test for ordering. A future commit will replace the existing
implementation of log with RevisionRange.

src/js/git/commands.js

@@ -574,6 +574,18 @@ var commandConfig = {
     }
   },
 
+  revlist: {
+    dontCountForGolf: true,
+    displayName: 'rev-list',
+    regex: /^git +rev-list($|\s)/,
+    execute: function(engine, command) {
+      var generalArgs = command.getGeneralArgs();
+      command.validateArgBounds(generalArgs, 1);
+
+      engine.revlist(generalArgs);
+    }
+  },
+
   log: {
     dontCountForGolf: true,
     regex: /^git +log($|\s)/,