add trademarking information

[orbeckst]

From MDAnalysis/mdanalysis-subprojects-branding#1 (comment) (@nicole-numfocus):

It would be good if you could add this line somewhere and also include the ™️ symbol with the logo.

"MDAnalysis™️ and the MDAnalysis logo are the sole property of NumFOCUS, Inc. (registration pending)."

Todo:

• update license files and readme
• update logo image files (??)

[orbeckst]

@nicole-numfocus I created this issue in our main branding repository as it is the central point for the core brand.

Could you please clarify the following?

With "also include the ™️ symbol with the logo." do you mean that the image files need to be changed so that the TM appears in the logo itself?

Can we do this while the registration is still pending or should we wait until it has been granted?