Tooltip

Fix #249 and #279
Another bug was found : there would be two select for each added inline element. The reason for that is that select2.js convert automatically element with class select2 [Code](https://github.com/PonteIneptique/docview/blob/bcb9b8e3659b11a465af8dd1f37eb7d26d7cb13c/modules/core/app/assets/js/admin.js#L155) (Which makes those lines useless if you ask me) or that another file do this and I didn't find it... The trick was to remove append select2 items [Code](https://github.com/PonteIneptique/docview/blob/bcb9b8e3659b11a465af8dd1f37eb7d26d7cb13c/modules/core/app/assets/js/admin.js#L187-L188) before adding select2.