Open-sources timelines.

    This represents the timelines plugin that was merged with the
    OpenProject core and which had its history squashed. The timelines
    plugin development was sponsored by;
    Deutsche Telekom AG <opensource@telekom.de>
    
    Requirements engineering and management were provided by;
    Deutsche Telekom AG <opensource@telekom.de>
    Finn GmbH <info@finn.de>
    
    During the timelines development, the following authors have contributed
    commits;
    Martin Czuchra <m.czuchra@finn.de>
    Nils Kenneweg <n.kenneweg@finn.de>
    Romano Licker <r.licker@finn.de>
    Gregor Schmidt <g.schmidt@finn.de>
    Jens Ulferts <j.ulferts@finn.de>
    Johannes Wollert <j.wollert@finn.de>
    
    Quality Assurance was provided by;
    Erdem Kabadayi <e.kabadayi@telekom.de>
    Julia Pape <j.pape@finn.de>
    Christian Rijke <c.rijke@finn.de>
    Thomas Vogel <th.vogel@external.telekom.de>