Doc updates for store locator and importer (#92)

docs/features/import_export.rst

@@ -20,3 +20,7 @@ generating software. Your CSV could look something like this::
 
 ``title``, ``address``, ``latitude``, ``longitude`` are all fields on your Page model that you will
 be importing as.
+
+.. note::
+    Your CSV file must be encoded as ASCII or UTF-8.
+    UTF-8-BOM will cause an error.

docs/features/store_locator.rst

@@ -43,4 +43,7 @@ Next run ``python manage.py makemigrations website`` and ``python manage.py migr
 the new pages in your project.
 
 Now when going to the wagtail admin, you can create a Location Index Page, and child Location Pages.
-Also be sure to add a Google Maps API key under Settings > Google API Settings.
+Also be sure to add a Google Maps API key under Settings > Google API Settings.
+
+.. note::
+    Before creating or importing location pages, add your Google API key for automatic geolocation.