Support including other config files from a config file

See merge request redox-os/installer!29

This will allow significantly reducing the amount of duplication
between all the different configs used by Redox OS.

This will be necessary to handle including other configs from the config
to use as these configs will not be copied.

This is no longer used since redox-os/redox!1397

Create symlinks before installing packages

See merge request redox-os/installer!27

This allows redirecting the location packages are installed using
symlinks. This makes it much easier to change the filesystem hierarchy
by not having to change every recipe in the cookbook.

add option for variable size of EFI system partition

See merge request redox-os/installer!26

Allow package spec "binary" or "recipe" to override REPO_BINARY=0 or REPO_BINARY=1

See merge request redox-os/installer!25

config: misc changes for GPU drivers

See merge request redox-os/installer!23

Signed-off-by: Anhad Singh <andypythonappdeveloper@gmail.com>

Update pkgar to 0.1.10

See merge request redox-os/installer!22

Update installer to use redoxfs unmount function

See merge request redox-os/installer!21

This fixes completing the image build on gentoo and MacOS.

Update Cargo.toml

See merge request !20

fix mixed build in a new clone

See merge request !19

Add ability to read package = recipe from filesystem config

See merge request !18

Remove unused imports and function

See merge request !17