Introducing the asset of type file creation. This involves making a
node collection entry of type asset, as well as a file collection
entry, plus all the needed variations if such file is an image or a
video. Further, depending on the storage backend (pillar or other) we
synchronise the files there using rsync. Currently this functionality
is available only via pillar-web, since a web interface is needed to
upload the file in a storage folder, which is shared between the two
applications.
We updated the way files are stored in the files collection. Any
derived variation of a file (different encoding or size) is stored as
new record, referencing the original as a parent.
We also added a generate_link method, which is in charge of providing
the client API with the actual link to the backend specified by the
file.
