Work around BucketAlreadyOwnedByYou

Buckets outside of the standard region will raise an error if you try
create them and they already exist. See:
https://forums.aws.amazon.com/thread.jspa?threadID=119095

flask_s3.py

@@ -184,7 +184,14 @@ def create_all(app, user=None, password=None, bucket_name=None,
     conn = S3Connection(user, password) # connect to s3
     # get_or_create bucket
     try:
-        bucket = conn.create_bucket(bucket_name, location=location)
+        try:
+            bucket = conn.create_bucket(bucket_name, location=location)
+        except S3CreateError as e:
+            if e.error_code == u'BucketAlreadyOwnedByYou':
+                bucket = conn.get_bucket(bucket_name)
+            else:
+                raise e
+
         bucket.make_public(recursive=True)
     except S3CreateError as e:
         raise e