Disable automatic "lang" attribute setting

[jonaswascheroh]

Is your feature request related to a problem? Please describe.
I am using this library for an embedded widget that is integrated into other companies websites.
I only just realized now that this library is automatically setting the "lang" attribute on the html tag, whenever the internalLocale is changed.
This is mixing up our customers websites.

Describe the solution you'd like
I would like to have the option in the init method to disable the automatic attribute setting.

How important is this feature to you?
Very important as there is currently no other way to do it.