for 0.8 release, a few more sentences translated, also revised some other sentences translation for easier understanding

updates #123

Now that the toggle is hidden when the controlbox is visible.

add more pt_BR translations and some fixes

Remove the "on" prefix. Events are listened to via "on" method, so it's
redundant.

Data is now by default cached in sessionStorage and not localStorage.
Can be configured via the "storage" option.