update version info

Author: jefferyUstc

setup.py

@@ -7,7 +7,7 @@
 
 setuptools.setup(
     name="python_dotplot",
-    version="0.0.1a1",
+    version="0.0.1b1",
     author='jefferyUstc',
     author_email="jeffery_cpu@163.com",
     description="light weighted dotplot drawer",