Implement Unit Tests

- Resolves import errors.

See Issue: MikeMeliz#16

modules/tests/__init__.py

@@ -0,0 +1,3 @@
+from modules import checker
+from modules import crawler
+from modules import extractor

modules/tests/test_checker.py

@@ -1,9 +1,9 @@
 import os.path
 import unittest
 
-from ..checker import extract_domain
-from ..checker import folder
-from ..checker import url_canon
+from modules.checker import extract_domain
+from modules.checker import folder
+from modules.checker import url_canon
 
 
 class TestCheckFunctions(unittest.TestCase):

modules/tests/test_crawler.py

@@ -1,10 +1,10 @@
 import shutil
 import unittest
 
-from ..crawler import Crawler
-from ..checker import url_canon
-from ..checker import extract_domain
-from ..checker import folder
+from modules.crawler import Crawler
+from modules.checker import url_canon
+from modules.checker import extract_domain
+from modules.checker import folder
 
 
 class TestCrawlerFunctions(unittest.TestCase):