[gi-docgen] (5 commits) Non-fast-forward update to branch wip/carlosg/multi-content-dir

[Carlos Garnacho <carlosg src gnome org>]

The branch 'wip/carlosg/multi-content-dir' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  44a9cb2... utils: Add helper method to lookup an extra content file
  667c7a3... genindices: Handle multiple --content-dir arguments
  10dd921... gendeps: Handle multiple --content-dir arguments
  a083e77... generate: Handle multiple --content-dir arguments
  9680876... docs: Document --content-dir as a multi argument

Commits added to the branch:

  b390c78... utils: Add helper method to lookup an extra content file
  839a0a0... genindices: Handle multiple --content-dir arguments
  8e115f1... gendeps: Handle multiple --content-dir arguments
  9bd1ea1... generate: Handle multiple --content-dir arguments
  b58e939... docs: Document --content-dir as a multi argument