Ability to customise UI header and footer text

[jonnyry]

As a TRE administrator I would like to be able to customise the header and footer text in the TRE portal via deployment variables so that I can display organisational and environment specific information.

[tim-p-allen]

Would be good to have a configurable logo too.

[marrobi]

@jonnyry is this similar to this one? #3809

[marrobi]

And this one #2851

[jonnyry]

And this one #2851

It's a duplicate of this one, will close.