Updates for 3.21.0
- +3.21 / -3.17
- remove unimplemented image_compress
- update TODO.md
- add IMPORTING.md
- remove deprecated get_latest_imported_tags
- set up gpio_pl06 for all aarch64
- recent cloud-init can use dhcpcd just fine
- always install non-busybox mount for 3.18+ (base/5.conf)
- tiny-cloud >= 3.1.0 does autodetection
- AWS & Azure images can use the same VHD format options
- nvme module is already enabled in cmdline/initramfs
- drop AWS NVMe core timeout setting for 3.21+
- switch GCP image format to "raw.tar.gz"
- enable GCP "gve" module on cmdline/initramfs
- drop setting "ntp_server", chrony will use default
- "generic" cloud should include all options for other clouds
- "generic" tiny-cloud starts with 3.21 (because of autodetection)
- move "sudo deprecated/removed" motd's out of version and into base configs
- cmdline console= for both x86_64 and aarch64 moved to base/1.conf
- ImageConfig.CONVERT_CMD resize raw image to 1 GiB before tar.gz
- ImageStorage.run() optionally supports shell string instead of individual args (for multi-step image conversions)
- don't disable getty on tty1 for those who need to login via VGA terminal (nocloud, etc?)