update readme about fork

README.mkd

+about the fork
+=========
+
+- Forked from https://github.com/dgrtwo/ParsePy on 3/28 by @milesrichardson
+- upstream seems to be no longer maintained
+- major fixes in fork:
+  - (improvement) Work with self-hosted parse-server
+  - (improvement) Work with self-hosted parse-server and batch_save
+  - (bugfix) batch_save calls response callback on ALL responses, even if some contain errors, and raises ParseBatchError([error1, error2, error3]) with list of all errors encountered during batch operation
+
+(See https://github.com/dgrtwo/ParsePy/pull/138 for PR)
+
 parse_rest
 ==========