fix upstream ref in ReleaseProcess.md

Author: manuzhang <owenzhang1990@gmail.com>

Closes #64 from manuzhang/fix_doc.
diff --git a/ReleaseProcess.md b/ReleaseProcess.md
index 5cf7536..4ecf460 100644
--- a/ReleaseProcess.md
+++ b/ReleaseProcess.md
@@ -26,7 +26,7 @@
 Step2: Release
 ==================
 1. Create a tag by ```git tag RELEASE_VERSION```
-2. ```git remote add upstream https://github.com/gearpump/gearpump.git```
+2. ```git remote add upstream https://github.com/apache/incubator-gearpump```
 3. ```git push upstream RELEASE_VERSION```
 
 Step3: Post-Release