rewrite cli errors

consistent order for arguments to load functions
refactor find_app_by_string to flow better
more cli loader tests

tests/test_apps/cliapp/factory.py

@@ -13,3 +13,7 @@ def create_app2(foo, bar):
 
 def create_app3(foo, script_info):
     return Flask('_'.join(['app3', foo, script_info.data['test']]))
+
+
+def no_app():
+    pass