rebuilderd v0.27.0 released

[kpcyrd]

Dear list,

I've tagged v0.27.0 of rebuilderd and started preparing packages:

https://github.com/kpcyrd/rebuilderd/releases/tag/v0.27.0

## Improved .udeb support

This release is mostly about a refactor of the `component` field (formerly 
referred to as `suite` in older rebuilderd releases, and commonly used for 
`core`/`extra` in Arch Linux, and `main` in Debian).

With this refactor, `component` is not a property of the source package anymore, 
but of the binary package, allowing a source package to have binary packages in 
multiple components.

This change was needed to improve .udeb supoprt, which is used by the Debian 
installer.

## Breaking changes in pkg sync configuration

It's likely also going to be the last release with the old `suite=` and 
`architecture=` settings, that were replaced with `components=` and 
`architectures=` respectively, but are currently still present for backwards 
compatibility.

Due to the way `components=` now works, operators may need to merge profiles, 
e.g. having an archlinux-core and archlinux-extra profile at the same time is 
not going to work anymore, those need to be merged into one profile.

## Manual cleanup needed for Arch Linux instances

Also (mostly affecting Arch Linux) I noticed the sync architecture was applied 
to all binary packages, meaning packages found in `core/os/x86_64/core.db` 
always had architecture=x86_64, even if they were technically architecture 
independent `any` packages.

With this fix in place however, it's now creating a second, duplicate package, 
meaning the previous package needs to be removed.

The new rebuilderd package is currently available in the [extra-testing] 
repository. Note the Arch Linux package is upgraded from v0.25.0 -> v0.27.0, 
please be patient with the database migrations on first restart and make 
yourself familiar with the breaking changes in v0.26.0 too:

https://github.com/kpcyrd/rebuilderd/releases/tag/v0.26.0

Sincerely,
kpcyrd