feat: allow to skip server integrity check before deploy

[SleepWalker]

This issue was already created on the old shipit-deploy repository, but probably an author have not transferred the code here:

#66
shipitjs/shipit-deploy#162

I'm planning to implement similar option, but it should work only for new releases. During rollback it should fail as always.

Another one case, that should be probably handled is copy of file from previous release. If we will add a fresh new host in the pool, it will be totally empty and there will be no release to copy from. So we should just skip cp for that host. Looks like this may be related to #213