Add AjaxOptOut

[Zeichen32]

@lippoliv If you agree, we can add this feature in this plugin, so users don't need to install two plugins for customizing the optout.

Reference to:
matomo-org/matomo#2896 (comment)

[lippoliv]

Hey @Zeichen32 sorry for the late reply, I don't use GitHub often :/

Yes of course you could implement it to your Plugin :)