XWIKI-9720: Use WikiStream by default in XAR import action
XWIKI-9379: Importing a XAR that contains a document called "null" does not work
[misc] Add toString() implementation
XWIKI-9720: Use WikiStream by default in XAR import action
XWIKI-9379: Importing a XAR that contains a document called "null" does not work
Merge branch 'feature-xarimportwikistream'