Revert "Add map.panBy() example"

This reverts commit df076eff9fc1b1b50ddfc8d02f352903de3695ec.
Revert "Revert "Add map.panBy() example""

This reverts commit dfdf52b5b654ff1c15dca56e55789b863b2b4495.
I think this commit fix the bug for iOS #222
Merge branch 'dev' into test