Rename to drf-yasg

drf-swagger was already taken

src/drf_yasg/errors.py

@@ -0,0 +1,14 @@
+class SwaggerError(Exception):
+    pass
+
+
+class SwaggerValidationError(SwaggerError):
+    def __init__(self, msg, validator_name, spec, source_codec, *args):
+        super(SwaggerValidationError, self).__init__(msg, *args)
+        self.validator_name = validator_name
+        self.spec = spec
+        self.source_codec = source_codec
+
+
+class SwaggerGenerationError(SwaggerError):
+    pass