slaprunner: add home directory reference.

Allows HOME to be easily referenced in some cases where buildout:directory is not available.
slaprunner: Make importer script process instances before running after-import subscripts.

Import script of webrunner asks stop of all instances, runs slapos, runs
consistency checks, runs scripts, ask start of all instances.
wip: Webunner: Make webrunner import script report in a file if import / afterimport was ok + make promise checking this
ERP5 SR: Use mariadb backup from erp5-cluster.

Side effect: activate binlogs.
current backup system does not work.
erp5: add resiliency exclude files.
erp5: add webrunner resiliency after-import (restore) scripts.
hardcode.
erp5: add tidstorage backup promise
erp5: add mariadb webrunner resiliency after-import (restore) script.
wip-maria import/promise
wip mariadb import/promise
wip import/promise
wip import/promise
wip: Add in afterimport scripts of erp5 several checks about consistency (if not, script fails) (1/ remove promise from erp5, 2/ in after-import: raise if fail)

todo: md5sum.
fixup: after-import mariadb