Minor release to fix service account impersonation

lib/google/api_client/version.rb

@@ -22,7 +22,7 @@ if !defined?(::Google::APIClient::VERSION)
       module VERSION
         MAJOR = 0
         MINOR = 6
-        TINY  = 0
+        TINY  = 1
         STRING = [MAJOR, MINOR, TINY].join('.')
       end
     end