[libsecret] (14 commits) Non-fast-forward update to branch wip/dueno/backend

[Daiki Ueno <dueno src gnome org>]

The branch 'wip/dueno/backend' 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:

  4e6d882... secret-retrievable: New interface to represent read-only it
  979fed0... secret-item: Implement SecretRetrievableInterface
  20ee96e... secret-password: Add search functions
  cddc874... secret-password: Add lookup_binary functions
  29ed765... secret-password: Add store_binary functions
  d51a2d1... secret-value: Add secret_value_unref_to_password
  f7b5f3c... tests: Add tests for binary variant of secret_{lookup,store
  b6edeea... secret-tool: Switch to using the simple API
  b0eebed... secret-service: Move parent property setting to constructor
  7608084... secret-backend: New interface to represent password storage
  42a358d... secret-service: Implement SecretBackendInterface
  f668592... secret-backend: Add a way to uncache singleton instance
  5c052fe... secret-password: Port to SecretBackend interface

Commits added to the branch:

  64e8c76... secret-retrievable: New interface to represent read-only it (*)
  777b304... secret-item: Implement SecretRetrievableInterface (*)
  7a8d152... secret-password: Add search functions (*)
  facfb0f... secret-password: Add lookup_binary functions (*)
  a3a7af6... secret-password: Add store_binary functions (*)
  1a298ea... tests: Add tests for binary variant of secret_{lookup,store (*)
  85565d2... secret-value: Add secret_value_unref_to_password (*)
  f71f968... secret-password: Mark @schema argument nullable for *v func (*)
  d3ff8a9... secret-tool: Switch to using the simple API (*)
  7d993af... secret-service: Move parent property setting to constructor
  c2f8aaa... secret-backend: New interface to represent password storage
  ae2d181... secret-service: Implement SecretBackendInterface
  5986376... secret-backend: Add a way to uncache singleton instance
  56c2fc8... secret-password: Port to SecretBackend interface

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