Improve update phase at indexation of GIT objects
Improve update phase at indexation of GIT objects

When multiple project shared a common set of commits
then the indexer used to delete then create the objects
in EL vith the bulk API. After some tests it seems slower
than using the bulk API to update only the specific field.
Tests shown x6 speed improvements.

Change-Id: Ie104c9c013ab6ab1341fe6a3bad0d61ee2a1121e

morucci/repoxplorer,morucci/repoxplorer,morucci/repoxplorer,morucci/repoxplorer