Implementing file like object accss to VSI files.
Implementing cache context
Implementing self referencing of packages.
Improving interfaces and BackendComponent.
Implementing Components for storage and package access. Implementing backend access functions.
Implementing Components for storage and package access. Implementing backend access functions.
implementing basic tests for backends.
Merge branch 'master-data-models' of git+ssh://github.com/EOxServer/eoxserver into master-data-models