change version to 0.9.0 for pending release

Author: wbarnha

setup.py

@@ -48,7 +48,7 @@
 
 setup(
     name="faust-streaming-rocksdb",
-    version='0.8.0',
+    version='0.9.0',
     description="Python bindings for RocksDB",
     keywords='rocksdb',
     author='Ming Hsuan Tu',