removes tukui support

[torkus]

• [x] addons from tukui can not be updated
  • catalogue/host-disabled? and catalogue/expand-summary
• [x] gui, update warning when tukui addons found
• [x] config, remove tukui catalogue from user config
• [x] tukui catalogue should not be generated
  • see strongbox-catalogue-builder
• [x] tukui addons should not be present in full and short catalogues
  • see strongbox-catalogue-builder
• [x] addons from tukui can not be imported
  • this will occur naturally when tukui addons are not present in any catalogue
    • non-github, non-gitlab addons consult the catalogue to find the addon before importing it to fill in the missing gaps in data.
  • disable anyway
  • see core/find-addon
• [x] tukui should not be present in emergency catalogue
  • this will occur naturally when tukui addons are not present in any catalogue
  • see core/emergency-catalogue
• [x] user catalogue, filter out any tukui addons on reading catalogue
  • otherwise they will appear in search results, will be importable.
  • see core/get-user-catalogue
• [x] disable source switching to tukui.
  • see addon/merge-toc-nfo to remove curse and tukui from the available 'source-maps'
• [x] disable bulk imports of tukui addons
  • see core/import-exported-file
• [x] update README
• [x] review
• [x] update CHANGELOG