[API Refactor] Add HTML reporting

Write HTML reports of test successes/failures to simplify
handling of test failures; pre-existing HTML test runner
is incompatible with changes to the way bundles are loaded.

karma.conf.js

@@ -55,7 +55,7 @@ module.exports = function(config) {
         // Test results reporter to use
         // Possible values: 'dots', 'progress'
         // Available reporters: https://npmjs.org/browse/keyword/karma-reporter
-        reporters: ['progress', 'coverage'],
+        reporters: ['progress', 'coverage', 'html'],
 
         // Web server port.
         port: 9876,
@@ -79,6 +79,11 @@ module.exports = function(config) {
             dir: "target/coverage"
         },
 
+        // HTML test reporting.
+        htmlReporter: {
+            outputDir: "target/tests"
+        },
+
         // Continuous Integration mode.
         // If true, Karma captures browsers, runs the tests and exits.
         singleRun: true