Bugfix: OcTextInput: Fix event handlers in loops

We pass all event handlers specified on `OcTextInput` to the underlying `input` element
except for `input`, `change` and `focus` event handlers. We fixed an issue in this exclusion
code that made `change`, `input` and `focus` handlers be re-registered on rerenders, particularly
in loop rerenders, so they were called multiple times for a single event.


https://github.com/owncloud/owncloud-design-system/pull/2054
