This is a completely unsupported port of openstack.net to .net standard.
I have only done this because the Rackspace support for .net is so out of date and I have an urgent need to port an existing app from another language to .Net that uses Rackspace for storage.
Please note I have only tested the CloudFiles APIs as they are all I need, so all bets are off on any parts of the library I do not use.
I hope this is useful to someone.
Please note there is still a dependency on SimpleRESTServices which is a .net 4.5 package, but I am using this in a .Net Core app and it seems to work okay. YMMV.