Synnefo

pithos: skip data directory creation until needed

Before this, when the pithos backend checked for the existence of a
data file (map or block) it also created its parent directories
if they did not exist, even though this is not needed until someone
actually decides to write the file....

cyclades: Fix typo bug in management command

Encrypt VM ids in the stats URLs

cyclades: Common filtering based on changes-since

Add 'filter_modified_since' function in snf_django api utils, for
parsing 'changes-since' HTTP parameter and filter the DB objects that
are updated after that date. Otherwise the deleted objects are returned.

Merge branch 'feature-pithos-atomic-api' into develop

pithos: backend.util pep8 fixes

cyclades: update plankton to commit pithos backend

The Pithos backend no longer auto-commits after each method invocation,
therefore plankton needs to handle transactions itself with with
pre_exec() and post_exec() methods.

cyclades: fix omitted plankton image properties

pithos: Cleanup api_method code

pithos: Optionally deactivate backend pooling

This is useful because the ``pithos.backends.lib.sqlite``
backend module is not compatible with pooling.

cyclades: Fix type error

Create network may return a list of job IDs.

cyclades: Fix wrong unit of ram

cyclades: Fix type error

Create network may return a list of job IDs.