Added this as a request and runs before auto start machines

fix(volumes): convert to qcow2 old raw bases

* test(volumes): upgrade old raw volumes

close issue #1385

fix(volumes): properly define backing files

* test(volumes); tries to rebase a volume
* test(volumes); create test qcow2 volumes
* refactor(volumes): base for qcow2 volumes is copy
* test(volumes): base from base

closes issue #1381

fix(nodes): remove volatiles reviewed

also fixed small bug showing clones in frontend

fixes issue #1345

fixes #1350

fixes #1350

feature(frontend): maintenance mode

issue #1310

issue #1345

issue #1345

refactor(nodes): use Net::OpenSSH

* refactor(frontend): removed plugin renderfile
* refactor(volumes): qcwo2 format on clones

issue #1153

Added Android template, new Ubuntu 20.04 ISOs and fixed arch

closes issue #1332 
fixes issue #1338 

Tested in 30_hardware.t

issue #1333

issue #1333

fix(frontend): update domain status after request

add test in 30_hardware.t

issue #1333

feature(backend): change number of started domains limit

closes issue #1166

feature(fontend): maintenance mode

closes issue #1331

fix(backend): checks node has enough memory

* refactor(test): now it only lists bases
* sets a minimal default memory if unset
* defaults to localhost if node full
* test fill memory

issue #1297

* feature(backend): auto shutdown disconnected
* feature(frontend): do not fetch data if not changed

issue #1276 

fix(KVM): unique MAC in all network cards

alwo test(KVM): check for duplicated MACs in 2nd eth

fixes issue #1294

* fix(backend): check volume name isn't already used

issue #1285

feat(settings): Shutdown all clones from settings

Issue #1287

issue #1271

issue #1271

* feature(backend): auto shutdown disconnected

issue #1280

feat(settings): Shutdown all clones from settings

Issue #1287