f-string changes for user, virt, vlan and vpn module

[JayasilanJibm]

This issue pertains to f-string notation changes from .format notation for user, virt, clan and vpn module.

This issue is created as a child issue for PR #1547

The following files/statement/expression have been modified to reflect the changes:

SoftLayer/CLI/user/list.py: user = _yes_format(user, [TWO_FACTO_AUTH, CLASSIC_API_KEYS])
SoftLayer/CLI/user/list.py:def _yes_format(user, keys):
SoftLayer/CLI/user/vpn_manual.py: message = "{} vpn manual config {}".format(user, 'enable' if enable else 'disable')
SoftLayer/CLI/user/vpn_manual.py: click.secho("Failed to update {}".format(user), fg='red')

SoftLayer/CLI/virt/cancel.py: env.fout("The virtual server instance: {} was cancelled.".format(vs_id))
SoftLayer/CLI/virt/create.py: click.secho('Warning: Closed soon: {}'.format(pod['name']), fg='yellow')
SoftLayer/CLI/virt/detail.py: last_transaction = "{} ({})".format(utils.lookup(result, 'lastTransaction', 'transactionGroup', 'name'),
SoftLayer/CLI/virt/dns.py: message = "{} does not have an ipv6 address".format(instance['fullyQualifiedDomainName'])
SoftLayer/CLI/virt/edit.py: env.fout("The {} of virtual server instance: {} was updated.".format(key, vs_id))
SoftLayer/CLI/virt/edit.py: env.fout("The public speed of virtual server instance: {} was updated.".format(vs_id))
SoftLayer/CLI/virt/edit.py: env.fout("The private speed of virtual server instance: {} was updated.".format(vs_id))
SoftLayer/CLI/virt/migrate.py: click.secho("Started a migration on {}".format(vsi_id), fg='green')
SoftLayer/CLI/virt/migrate.py: click.secho("Failed to migrate {}. {}".format(vsi_id, str(ex)), fg='red')
SoftLayer/CLI/virt/notification_delete.py: env.fout("The virtual server notification instance: {} was deleted.".format(identifier))
SoftLayer/CLI/virt/storage.py: "{capacity} {unit}".format(capacity=disk['diskImage']['capacity'],

SoftLayer/CLI/vlan/cancel.py: env.fout("VLAN {} was cancelled.".format(identifier))
SoftLayer/CLI/vlan/create.py: "Unable to find pod name: {}".format(pod))

SoftLayer/CLI/vpn/ipsec/cancel.py: env.fout("Ipsec {} was cancelled.".format(identifier))
SoftLayer/CLI/vpn/ipsec/configure.py: click.echo('Configuration request received for context #{}'.format(context_id))
SoftLayer/CLI/vpn/ipsec/configure.py: raise CLIHalt('Failed to enqueue configuration request for context #{}'.format(context_id))
SoftLayer/CLI/vpn/ipsec/detail.py: return '[mask[{}]]'.format(','.join(entries))
SoftLayer/CLI/vpn/ipsec/subnet/add.py: .format(subnet_type))
SoftLayer/CLI/vpn/ipsec/subnet/add.py: .format(network_identifier[0],
SoftLayer/CLI/vpn/ipsec/subnet/add.py: env.out('Added {} subnet #{}'.format(subnet_type, subnet_id))
SoftLayer/CLI/vpn/ipsec/subnet/add.py: .format(subnet_type, subnet_id))
SoftLayer/CLI/vpn/ipsec/subnet/remove.py: env.out('Removed {} subnet #{}'.format(subnet_type, subnet_id))
SoftLayer/CLI/vpn/ipsec/subnet/remove.py: .format(subnet_type, subnet_id))
SoftLayer/CLI/vpn/ipsec/translation/add.py: .format(static_ip, remote_ip, translation['id']))
SoftLayer/CLI/vpn/ipsec/translation/remove.py: env.out('Removed translation #{}'.format(translation_id))
SoftLayer/CLI/vpn/ipsec/translation/remove.py: raise CLIHalt('Failed to remove translation #{}'.format(translation_id))
SoftLayer/CLI/vpn/ipsec/translation/update.py: env.out('Updated translation #{}'.format(translation_id))
SoftLayer/CLI/vpn/ipsec/translation/update.py: raise CLIHalt('Failed to update translation #{}'.format(translation_id))
SoftLayer/CLI/vpn/ipsec/update.py: env.out('Updated context #{}'.format(context_id))
SoftLayer/CLI/vpn/ipsec/update.py: raise CLIHalt('Failed to update context #{}'.format(context_id))

The changes also include change from %s or %I string notation to f-string in few statements across these files.

Thanks,
Jayasilan