add teamsnap preferences page.

teamsnap/forms.py

@@ -0,0 +1,16 @@
+from django import forms
+from django.forms import ModelForm
+
+from .models import Preferences
+
+
+class PreferencesForm(ModelForm):
+    class Meta:
+        model = Preferences
+        fields = ["user", "managed_team_id"]
+        widgets = {
+            "user": forms.HiddenInput(),
+            "managed_team_id": forms.Select(
+                choices=(), attrs={"class": "form-control"}
+            ),
+        }