[core/engine] Add module loading logic

Allow the engine to load modules from the bumblebee/modules/ directory.

see #23

tests/test_engine.py

@@ -2,12 +2,33 @@
 import unittest
 
 from bumblebee.engine import Engine
+from bumblebee.config import Config
 
 class TestEngine(unittest.TestCase):
     def setUp(self):
-        self.engine = Engine(None)
+        self.engine = Engine(Config())
+        self.testModule = "test"
+        self.testModuleSpec = "bumblebee.modules.{}".format(self.testModule)
+        self.testModules = [
+            { "module": "test", "name": "a" },
+            { "module": "test", "name": "b" },
+        ]
 
     def test_stop(self):
         self.assertTrue(self.engine.running())
         self.engine.stop()
         self.assertFalse(self.engine.running())
+
+    def test_load_module(self):
+        module = self.engine.load_module(self.testModule)
+        self.assertEquals(module.__module__, self.testModuleSpec)
+
+    def test_load_modules(self):
+        modules = self.engine.load_modules(self.testModules)
+        self.assertEquals(len(modules), len(self.testModules))
+        self.assertEquals(
+            [ module.__module__ for module in modules ],
+            [ self.testModuleSpec for module in modules ]
+        )
+
+# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4