This reverts commit 885f81f3.

/reviewed-on !41

/reviewed-on nexedi/slapos.toolbox!40

/reviewed-on nexedi/slapos.toolbox!39

/reviewed-on nexedi/slapos.toolbox!38

/reviewed-on nexedi/slapos.toolbox!37

This solve indefinite loop in while condition on promise check_free_disk_space

check_free_disk_space is now in promise.plugin, with some improvement.
Database connection timeout is now 10 seconds
If database is locked, promise will try again 10 times before start to raise error with "database is locked" message.

When the URL /isSRReady is called if the software release link is not present in softwareLink folder, webrunner will launch build of software. The result is slapgrid trying to build sr every minutes, then resiliency fail.

Start slapproxy at runner startup and when instance is removed in webrunner. This fix resiliency problem when proxy.db file does not exist.

/reviewed-on nexedi/slapos.toolbox!36

resiliency data in instance_root/slappart0/var/log/log.log is writen by a service in slaprunner, so after the takeover
the service will start again an write a new entry. We should then check if data from old runner0 is present in new data log.

/reviewed-on !33