[gnome-boxes] (16 commits) Created branch wip/rishi/rhel

[Debarshi Ray <debarshir src gnome org>]

The branch 'wip/rishi/rhel' was created.

Summary of new commits:

  e6f4c1b... os-database, wizard-source: Use named constants, not magic 
  81ef0d0... util: Simplify code
  7a9575c... wizard, wizard-source: Use the headerbar to go back from "E
  4e5795e... wizard-source: Use 'requires' instead of 'assert'
  a4e6afb... wizard-source: Group the sources into local files, and ever
  2d8bcfc... wizard-source: Separate the groups of sources using heading
  7bdc8d1... wizard-source: Move the file selection button next to the h
  eb6a553... wizard-source: Align each page separately, instead of the w
  f8fd289... wizard: Let the WizardSource expand if it wants to
  8ffca7e... downloader, wizard: Support a custom filename for downloade
  5ced88c... wizard: Allow a custom filename when sanity-checking downlo
  7f094e1... wizard: Wire the custom filename to the URI validator
  87f88de... wizard: Wire the custom filename to the downloader
  3089963... configure: Require json-glib and webkitgtk+
  f169546... configure: Require gtk+ >= 3.22.20
  1ebbe35... wizard, wizard-source: Support gratis RHEL boxes