Update vote count wording.

Author: Marcelo Vanzin

dev/create-release/vote.tmpl

@@ -1,6 +1,7 @@
 Please vote on releasing the following candidate as Apache Spark version {version}.
 
-The vote is open until {deadline} and passes if a majority of at least 3 +1 PMC votes are cast.
+The vote is open until {deadline} and passes if a majority +1 PMC votes are cast, with
+a minimum of 3 +1 votes.
 
 [ ] +1 Release this package as Apache Spark {version}
 [ ] -1 Do not release this package because ...