CoLaBoot (Compressed Layers Boot) is a boot system that allow you to mount root
FS as OverlayFS from a separate layers, each of them is compressed squashfs image.

Layers can be aquired from network (HTTP(S)/FTP/TFTP/... any proto supported by
curl(1)), or from local filesystems (ISO/HDD). 

Multiple layer's locations supported, some of the layers may be optional for boot.
Layers placed on the local filesystems may be mounted directly, to avoid caching in
memory.

Kernel modules, required for boot (e.g. network modules) may be added to initrd
or provided as a separate initramfs image. All other modules may be provided as
one of the layers.

List of layers, arranged by boot order, with a some optional parameters described
in a text .manifest file (see examples).



Supported boot parameters:
root= - location of .manifest file, OR the only layer to boot. Examples:
	http://my.boot.server/path/my.manifest
	file:///sr0/isolinux/rootfs.squashfs

rootdelay= - maximum delay in seconds for many wait actions, such as wait for network
address, or block device initialization. 

clb_fs_size= - size for tmpfs. Default - 2G.

clb_use_iface= - use specific network interface for boot.

clb_force_cache_images= - if set to 0, disable caching in memory layers images,
accessible from local media (file:/// scheme in layer's URI). Default: 1.

clb_load_modules= - comma separated list of kernel modules, required to be
loaded. If some modules provided in separate initramfs image, we can't load them
via standard make-initrd ways (like MODULES_PRELOAD).

curlopts= - any options for curl.


Supported macroses in .manifest file or root= boot parameter:
{inherit} - only for .manifest file. Expanded into 'dirname'-part of the root='s URI

{DHCP_*} - any DHCP variable which you can find in a dump file, making by dhcpcd -U.
Examples: {DHCP_dhcp_server_identifier}, {DHCP_ip_address}

