Reduce swap partition size

Use explicit schema to create partitions. Swap partition was to large
with the automatic partitioning (ie. 8 of 20 GB). Now swap partition is
arround 1 GB.

SMBCAP-4718
Adjust swap and /boot for storage

Increase /boot so we can have more kernels installed in parallel and
reduce swap partiton.
Adjust partiton values for VMs
Adjust partitions for compute preseed
Merge pull request #11 from TelekomCloud/bug/SMBCAP-4718_decrease_swap_partition_size

Reduce swap partition size