Imeji version management

 Work in progress

Status

 * Not implemented
 * Nb: The version metadata are available, but the version management is not implemented yet in imeji

use cases
The version management uses the following model (inspired by the dublin core schema). The labels of the table below are explained in imeji/properties

Note:
 * When an object is released, it gets a date issued. The next version is created only when used wants to revise/modify the last released version.

Technical description

 * the version management is implemented via the imeji/properties