Add logo and its licence / AUP to HIFIS media page

Original request from @Normo

Would it be possible to provide HIFIS logos (together with license information) on our website e.g. https://hifis.net/media? (A non-HIFIS colleague asked me if and how he could use the HIFIS logos in a presentation.)

To-do:

• define acceptable use policy and licence (?) of HIFIS logos
• add to https://hifis.net/media (indeed seems like the most natural place)