[gimp-web] (17 commits) ...Merge branch 'testing'

[Pat David <patdavid src gnome org>]

Summary of changes:

  16cd973... Add rotating header image javascript (*)
  3636f23... Add extra css for non-js users to still see background img (*)
  f540417... Fix typo (*)
  cf284ca... Add !important to js generated style for bg img (*)
  e6890be... Add pre-caching for other header images (*)
  715ed5c... Merge branch 'header-image' into testing (*)
  1f5c326... Add <noscript> around default header img for non-js users (*)
  d07f973... Merge header-image after adding a <noscript> around default (*)
  dc7399e... Try a fix for CSP vs. rotate-header-image (*)
  95de91b... Merge branch 'header-image' into testing (*)
  71e1fb6... Mention pippin's and Jehan's fundraisers (*)
  2e1f5c2... Add different style line for header (*)
  d2e24f5... Merge branch 'header-image' into testing (*)
  c8f3e34... Fix some minor typos and grammar (*)
  d292f31... Merge branch 'donate' into testing (*)
  f1ccb37... Try to speed up header image loading a little (*)
  4e18407... Merge branch 'testing'

(*) This commit already existed in another branch; no separate mail sent