Increase default timeout to 5 seconds from 2

This is arbitrary, and we could increase it more or make it configurable via
the command line if Travis continue to time out, but this allows all tests to
complete for me in a VM.

test/content/runtests.js

@@ -70,7 +70,11 @@ function Reporter(runner) {
 }
 
 // Setup Mocha
-mocha.setup({ui:"bdd", reporter:Reporter});
+mocha.setup({
+	ui: "bdd",
+	reporter: Reporter,
+	timeout: 5000
+});
 
 // Enable Bluebird generator support in Mocha
 (function () {