Adding core and libraries mock classes
diff --git a/tests/mocks/libraries/useragent.php b/tests/mocks/libraries/useragent.php
new file mode 100644
index 0000000..c957cde
--- /dev/null
+++ b/tests/mocks/libraries/useragent.php
@@ -0,0 +1,3 @@
+<?php
+
+class Mock_Libraries_UserAgent extends CI_User_agent {}
\ No newline at end of file