Use the extension and authentication in the namespace browser tests.

This required moving/refactoring some of the test logic.  The
servicerunner binary is used to start the proxy, root mounttable, and
identity server.  All the binaries are built in the Makefile's "go/bin"
task.

I added a test for globbing on a rooted host:port mounttable.

Change-Id: I4dc8e24666ea0ca6e54bc1eda89f070643ccd8f8
diff --git a/package.json b/package.json
index 4fc2986..e27c178 100644
--- a/package.json
+++ b/package.json
@@ -18,7 +18,8 @@
     "vulcanize": "^0.3.1",
     "postie": "~0.4.5",
     "lru-cache": "~2.5.0",
-    "tap-xunit": "~1.1.1"
+    "tap-xunit": "~1.1.1",
+    "envify": "~3.2.0"
   },
   "dependencies": {
     "bars": "git+https://github.com/steel/bars.git",