Set version to 0.8.1 on release branch.

dstrain115 · dstrain115 · commit ed175bcd1179 · 2020-06-03T13:44:45.000-07:00
diff --git a/cirq/_version.py b/cirq/_version.py
@@ -28,4 +28,4 @@
         'B) Explicitly install an older deprecated-but-compatible version '
         'of cirq (e.g. "python -m pip install cirq==0.5.*")')
 
-__version__ = "0.8.1.dev"
+__version__ = "0.8.1"
