ssh: set connection timeout to 10s
ssh: set connection timeout to 10s

We currently don't specify any explicit connection timeout for SSH
invocations. In many cases, SSH may wait up to 2 minutes (or even more)
before bailing out on an unreachable node, which may cause unwanted
side-effects, like RPC timeouts. Since connecting via SSH to a node
should never take too long, setting ConnectTimeout to 10s universally
seems like a good and arguably conservative default.

This fixes #1286.

Signed-off-by: Apollon Oikonomopoulos <ed81ed0a45ccd5c8869bda52e38353a6299ee39e@debian.org>

ganeti/ganeti,mbakke/ganeti,ganeti/ganeti,ganeti/ganeti,mbakke/ganeti,mbakke/ganeti