XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Fix bug.
XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Perform a better migration of Workspace Candidacies.
XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Remove useless injects!
XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Migration of Workspaces: Add the restoration of pages that was previously deleted by WorkspaceManager.Install.
XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Migration of Workspaces: Add the restoration of pages that was previously deleted by WorkspaceManager.Install.
XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Migration of Workspaces: Fix tests.
XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Migration of Workspaces: Fix style
XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Migration of Workspaces: Add the restoration of pages that was previously deleted by WorkspaceManager.Install.
Merge remote-tracking branch 'upstream/master' into new-wiki-api

Conflicts:
	xwiki-platform-core/xwiki-platform-wiki/xwiki-platform-wiki-user/xwiki-platform-wiki-user-default/src/main/java/org/xwiki/wiki/user/internal/WikiUserClassDocumentInitializer.java
XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Migration of Workspaces: Add the restoration of pages that was previously deleted by WorkspaceManager.Install (bug fix).
XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Migration of Workspaces: Add the restoration of pages that was previously deleted by WorkspaceManager.Install (bug fix).
XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Migration of Workspaces: Bug fix.
XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Fix descriptor cache bug.
* Add extension names in POMs.
XWIKI-9516: Create a new Wiki API that replaces xwiki-platform-wiki-manager and xwiki-platform-workspace.

* Fix migrator.
XWIKI-9738: Finalize migration from workspaces to the new wiki API.

* Deleting the old workspace object at the very end of the migration, in order to be able to resume the migration when it is stopped.
Merge pull request #222 from gdelhumeau/XWIKI-9738

XWIKI-9738: Finalize migration from workspaces to the new wiki API.