build: Use mirrorlist to fetch installer images

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
spec: Fix python file inclusion

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
imgbase: Move to log()

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
imgbase: Add diff

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
imgbase: Add nspawn

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
imgbase: Add experimental support for syslinux

Previously imgbased used BLS config files to install new boot entries,
the problem with this approach is that BLS does not allow to set a
default entry.
Now the syslinux configuration file format is used to specify the
bootloader configuration. This format allows to set the default boot
entry to be booted.

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
ks: Add syslinux grub support

Requires a recent grub build

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
imgbase: Restructure to be plugin based

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
imgbase: Further modularize and pluginify

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
imgbase: Add remote support

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
imgbase: Add bootloader management support

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
imgbase: Add context to hooks

Now all handlers automatically receive a context as well.
In imgbase the context is the application.
Further more fs-based handlers are only called for hooks in imgbase.

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
Merge branch 'pluginified'

This will delegate some functionality to plugins.
This will also enforce to add hooks t be able to extend the
functionality.