improve UI framework

[mgerhold]

This should include:

• general improvement in components, that can render individually Improve Scenes and UI library #115
• layouts of components, like grid_layout, tile_layout etc. Improve Scenes and UI library #115
• relative and absolute positioning Improve Scenes and UI library #115
• more components:
  • slider Improve Scenes and UI library #115
  • scroll_list Add experimental obpf/lobby support #121
  • keybinding setter
  • text input Improve UI library #128
  • image container Add info (about) page #119
  • popup Add Color Picker Component #138
  • wrapped_text
  • hyperlink_text Add info (about) page #119
  • tooltip
  • image button Add Color Picker Component #138
  • color picker Add Color Picker Component #138
  • spinner (indeterminate) Feat: Render recording #205
  • progressbar (normal)