Improved error reporting when started teleport
Improved error reporting when started teleport

Before:

Without "--debug" flag teleport would not report some errors to stderr.
A user would get the impression it's working properly.

After:

Initialization errors are dumped into cfg.Console writer, just like we
do everywhere else, so errors are duplicted in the log and also in the
user-facing console.

gravitational/teleport,yacloud-io/teleport,yacloud-io/teleport,tidalf/teleport,gravitational/teleport,gravitational/teleport,sokoow/teleport,yacloud-io/teleport,sokoow/teleport,sokoow/teleport,aashley/teleport,aashley/teleport,ajvb/teleport,bshelton229/teleport,gravitational/teleport,tidalf/teleport,gravitational/teleport,tidalf/teleport,suedadam/teleport,suedadam/teleport,bshelton229/teleport,sokoow/teleport,tidalf/teleport,sokoow/teleport,aashley/teleport,bshelton229/teleport,ajvb/teleport,ajvb/teleport,aashley/teleport,suedadam/teleport,aashley/teleport,yacloud-io/teleport,ajvb/teleport,yacloud-io/teleport,yacloud-io/teleport,suedadam/teleport,yacloud-io/teleport,tidalf/teleport,ajvb/teleport,bshelton229/teleport,suedadam/teleport,sokoow/teleport,bshelton229/teleport,gravitational/teleport