Handle Studio project dependency packages

An issue occurred when updating a Studio project in the platform when the project has dependencies to download.

In both cases, the Studio project has been defined for target platform 6.0 with the packages DAM and Virtual Navigation activated. The connection to the Studio project is done in the wizard when configuring the platform.

Using a Nuxeo 6.0 with the development mode deactivated

• in Admin tab, update the Studio project ==> a popup display an error message stating that two packages must be downloaded (expected behavior)
• click on 'Update anyway' and restart the server
• after restart, the packages DAM and Virtual Navigation are downloaded, it works fine

Using a Nuxeo 6.0 with the development mode activated

• in Admin tab, update the Studio project ==> a popup display an error message stating that two packages must be downloaded (expected behavior)
• click on 'Update anyway' and restart the server
• after restart, only the package DAM is downloaded but not the Virtual Navigation one

The file package.xml has the proper dependencies defined.