Bump version number post-release.

webtools/bugzilla/Bugzilla/Constants.pm

@@ -156,7 +156,7 @@ use File::Basename;
 # CONSTANTS
 #
 # Bugzilla version
-use constant BUGZILLA_VERSION => "3.1.3";
+use constant BUGZILLA_VERSION => "3.1.3+";
 
 # These are unique values that are unlikely to match a string or a number,
 # to be used in criteria for match() functions and other things. They start