inital commit for signup

added a basic app using the UserCreationForm to create new user at /accounts/signup/
change outside of the app are:
-added signup to INSTALLED_APPS in /photo21/settings.py
-added accounts/signup/ to path in /photo21/urls.py

should extend UserCreationForm to have field for email and maybe first/last names, except if we want the user to add that themselves later

signup/settings.py

@@ -0,0 +1,8 @@
+import os
+BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+TEMPLATES = [
+    {
+        'DIRS': [os.path.join(BASE_DIR, 'photo21/signup/templates')],
+        'APP_DIRS': True,
+    },
+]