Disable actx.clone on discr.copy (#293)
* disable actx.clone on discr.copy
* Better explain actx cloning logic in Discretization constructor
Co-authored-by: Andreas Klöckner <inform@tiker.net>
* disable actx.clone on discr.copy
* Better explain actx cloning logic in Discretization constructor
Co-authored-by: Andreas Klöckner <inform@tiker.net>