* EDIT: Fixed linting errors.

* Added image_details property to source.
* Allowed for the specification of additional file extension maps to MIME types, including support for no file extension.
* Modified filename_filter to be interpreted as a complete list of files to look for and include, preventing  glob of entire directory.
* Added error-checking for empty (no images included) UploadableSources.

zegami_sdk/source.py

@@ -102,6 +102,7 @@ def image_details(self):
 
         return ims
 
+
 class UploadableSource():
 
     IMAGE_MIMES = {
@@ -129,7 +130,8 @@ class UploadableSource():
         ".json"
     )
 
-    def __init__(self, name, image_dir, column_filename='__auto_join__', recursive_search=True, filename_filter=[], additional_mimes=None):
+    def __init__(self, name, image_dir, column_filename='__auto_join__', recursive_search=True, filename_filter=[],
+                 additional_mimes=None):
         """
         Used in conjunction with create_collection().
 
@@ -150,7 +152,6 @@ def __init__(self, name, image_dir, column_filename='__auto_join__', recursive_s
         self._source = None
         self._index = None
 
-
         UploadableSource.IMAGE_MIMES = {**UploadableSource.IMAGE_MIMES, **additional_mimes}
 
         # Check the directory exists
@@ -446,4 +447,4 @@ def _upload(self):
         payload = json.dumps(upload_ims['imageset'])
         r = c._auth_put(upload_ims_url, payload, return_response=True)
 
-        return r
+        return r