XWIKI-10252: Add and/or edit objects in a page

* Rename variables for lisibility
XWIKI-10252: Add and/or edit objects in a page

* Change the name of the default policy (the one of the old core)
XWIKI-10252: Add and/or edit objects in a page

* Change the parsing of parameters using regular expressions
XWIKI-10252: Add and/or edit objects in a page

* Avoid 2 look-ups of the same information
XWIKI-10252: Add and/or edit objects in a page

* Use `entrySet()` loops instead of `keySet()` loops.
* Use a document resolver to find references
XWIKI-10252: Add and/or edit objects in a page

* Remove another 2-lookups in a same object