Added tippyjs-react for Tooltips

[narickmann]

• added and implemented tippyjs-react
• added tooltips where it makes sense
• removed unnecessary title-attributes (e.g. buttons where title-attribute and button-text was the same)
• added english translation for video-settings-button

[lkiesow]

Current state: https://test.studio.opencast.org/2022-05-16_13-43-27-pr931-2332299188/

[LukasKalbertodt]

I realize this is already merged, but some quick notes, maybe for a follow up PR:

• I would prefer if the tooltip would appear instantly instead of slowly getting visible. When disappearing a transition-effect is fine, but when appearing, it feels laggy IMO. And you can miss that there even is a tooltip.

• The tooltip over the video settings cog could be higher? It hides a bit of the cog even.

• There is still a fairly useless title attribute on the upload button, I think

Other than that, great work. Every element that could use a tooltip has one, and every element where a tooltip would be useless has none.