Replaced sessions collection upgrade task.
Fixed some data in the gitbook theme
Added "preprocess" to job type definitions.
Fixed wrong spelling in the errors
Return headers and body in ArangoClusterComm.syncRequest method.
Fixed the success callback for Queues

When an option was missing, the resulting String would have `, ,`
in the String to be evaluated which would result in a syntax error
Implemented crypto.jwtEncode/jwtDecode (HS256 only).
Added support for JWT alg: 'none'.
Linting.
Fixed destroySession docs.
css changes
added favicon to gitbook
changed the name of a link
document export bugfix, added filters to doc export function
Merge branch 'devel' of https://github.com/triAGENS/ArangoDB into devel
Implemented session.getExpiry, session.hasExpired.
issue #1000: AQL Editor: Autofocus textarea
issue #999: clear old result when submitting new query
hopefully fix random travis test
fix typo in manual