.gitlab/ci/build-inside-vm.sh:
Add `print_section_start()` and `print_section_end()` to remove code duplication when printing gitlab collapsible
sections (https://docs.gitlab.com/ee/ci/jobs/#custom-collapsible-sections).
Document further script dependencies.
Remove the temporary directory base (located in the project directory) instead of only the tempdir.
Simplify setting file and directory ownership when running with sudo, by only doing it once, recursively on the output
directory.
Make the script's output more verbose by using verbose flags for removal, ownership changes and zsyncmake actions and by
displaying e.g. created metrics and checksum files.
Change `create_metrics()` to output to a `metrics.txt` by default.
Change `create_checksums()` to create the checksums relative to the files.
.gitlab/ci/build-inside-vm.sh:
Expand the script to allow building based on mkarchiso's buildmodes.
Accept two parameters now: profile and buildmode.
Add gitlab collapsable sections by adding specific printfs for it to all functions.
Add extglob to be able to more specifically target files.
Change `create_checksums()` to also generate the legacy md5 and sha1 checksums.
Change `create_checksums()` and `create_zsync_delta()` to accept and process an unspecified amount of files as
parameters.
Change `create_zsync_delta()` to lower the blocksize when creating a file for the bootstrap image.
Change `create_metrics()` to create metrics depending on build mode.
Rename `create_temp_pgp_key()` to `create_ephemeral_pgp_key()`.
Add `create_ephemeral_codesigning_key()` to create a codesigning key, that is used to sign the netboot artifacts.
Change `run_mkarchiso()` to also create an ephemeral codesigning key before running mkarchiso and to run
`create_checksums()` and `create_zsync_delta()` with files depending on build mode.
.gitlab/ci/build-host.sh:
Call `build-inside-vm.sh` using the PROFILE and BUILDMODE environment variables as parameters.
.gitlab/ci/build-inside-vm.sh:
Create an ephemeral signing key for signing the rootfs image (e.g. squashfs or erofs) when building the profiles.
Implements #125
.gitlab/ci/build-host.sh:
Change the readonly TMPDIR variable to a global tmpdir variable and set it in the `init()` function.
.gitlab/ci/build-inside-vm.sh:
Change assigning the readonly tmpdir variable directly to assigning it after declaring it.
Change `cleanup()` and `create_zsync_delta()` to use bash-style statements and also check whether SUDO_GID is set before
using it.
.gitlab/ci/build-host.sh:
Add script to be run in a container with access to qemu.
It is a slight modification of arch-boxes' build-host.sh script to cater to the specific archiso requirements.
.gitlab/ci/build-inside-vm.sh:
Add script to be run in virtualized environment, established by build-host.sh.
This script builds the actual archiso profiles and creates checksum for the resulting image files.
