rkt: Don't require port_map with host networking

Do not emit logs on SIGPIPE since logging service could be unavailable

Emit hostname as a label

Support StopTimeout for Docker tasks

Also don't try to return a DriverNetwork with host networking. None will
ever exist as that's the point of host networking: rkt won't create a
network namespace.

Fix typos in metric names. #3610

UI Placement Failures & Evaluations

 Handle exact namespace match properly when also matched as prefix 

Sigh.

This reverts commits
141ecd8d
d2d838c2
8099db43
86262b3c
eb4104ec
0e0e23e2
6d45658d
b52a8176

Sigh.

This fixes an issue with the nomad namespace inspect and nomad namespace status commands failing to run for namespaces whose names are the start of another namespace's name: for example, foo and foobar. If the argument matches the first possibility returned by prefix exactly, that namespace will be targetted. If no exact match occurs, the behavior is unchanged.

Update github.com/fsouza/go-dockerclient

UI: Log streaming

Changed Superset to only return the resource name

Update community.html.erb to include Levant.