The version correspond to a JAR version that is required by some package. An update version is defined by the JAR
version, a relative path to the JAR file and a list of packages requiring this version. The path points to a copy of
the JAR version in the update manager storage. (thus the path is relative to the update manager root) Let say you
install a package pkg1 that requires the version 1.0 for the jar X. If this version is not yet provided by another
package a new version will be created and the jar file copied in the update manager storage under the destination
'path' (e.g. bundles/X-1.0.jar).