Content archiver - Asynchronous version

The first implementation of the archiver is synchronous (described in #240 (closed) and implemented in #400 (closed)). Adapt the code to make this asynchronous.

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Migrated from T401 (view on Phabricator)

mentioned in commit 0e84344d

mentioned in commit swh-archiver@1e3eb199

mentioned in merge request !41 (closed)

assigned to @qcampos

marked this issue as related to #400 (closed)

added 2016-06-30 Storage manager priority:Normal labels

marked this issue as related to #403 (closed)

marked this issue as related to #404 (closed)

marked this issue as related to #406 (closed)

closed

mentioned in commit f92426dd

mentioned in commit swh-objstorage@9bd27d2c

mentioned in commit swh-archiver@af2d9790

changed title from Asynchronous version to Content archiver - Asynchronous version

changed the description

mentioned in commit d5f02d4d

mentioned in commit swh-archiver@f86ab4d7

marked this issue as related to #512 (closed)