Increase socket timeout to 1 minute during bootstrap

We increase the socket timeout during bootstrap to
cope with slow disk I/O during machine initialisation.
Empirical evidence has shown this to decrease the
bootstrap failure rate on Microsoft Azure.

Fixes https://bugs.launchpad.net/juju-core/+bug/1351101
cmd/jujud: add test for InitializeState params
cmd/jujud: set socket timeout to bootstrap timeout
Merge pull request #463 from axw/lp1351101-bootstrap-longsockettimeout

Increase socket timeout to 1 minute during bootstrap

We increase the socket timeout during bootstrap to
cope with slow disk I/O during machine initialisation.
Empirical evidence has shown this to decrease the
bootstrap failure rate on Microsoft Azure.

Fixes https://bugs.launchpad.net/juju-core/+bug/1351101