default computer options groups from aiida_jutools ComputerOptionsManager (changes: iffslurm_options -> computer_options/iffslurm, default max_wallclock_seconds = 24h)

Update data/codes/fleur_iffslurm.aiida

See merge request aiida/aiida_nodes!1

Also move computer options and remove deprecated import files

Runs verdi computer configure and creates an automatic ssh-configuration for iffslurm

Add possibility to use access token from IFFDATA_ACCESSTOKEN environment variable in git_pull_from_iffgit

* we now use srun instead of mpirun for iffslurm
* for kkrhost we use the develop version until the next release is done
* delete voronoi@localhost since it does not work inside the iffaiida container