Add page on responsible OpenStack usage

[rvosa]

Specifically, add the following points:

• instances are assigned on a project basis, so no 'mission creep' where claimed resources are used for other purposes than stated in the original request
• instances need a specific name so that the scope and ownership is clear in the openstack panel (not transcriptome analysis but transcriptome analysis organism, owner)
• emphasize that instances can, and should, be turned off when not in use
• explain how instances can be stored as image files at project sundown if need be
• what to do with data volumes, as instances are glaciered, but volumes aren't