Update roadmap

We took a hard look at 1.0 and what things ae really REQUIRED to get to a
stable release that is "useful".  This required moving some things we thought
were really important but not CRITICAL down the list.

For now they are stricken from this doc, but I expect this doc to start
growing a "post 1.0" list soon.

Things stricken and why:

Using the host network: This is primarily a performance optimization, but it
causes potential problems with other uses of HostPorts.  We'd rather focus on
fixing perf problems than dodging them.  We can revisit later if there is a
strong case for it.

Representation of Ports in the Manifest structure: We discussed and decided
that, since HostPort semantics have changed, this matters less than before.

Scenarios where IP-per-pod is hard or impossible: We're still game to help
people figure out how to make it work, but we don't see a case for making k8s
1.0 work in a fundamentally different mode.  Too much churn and risk.  We can
revisit later, if needed.

Auto-scaling controller: We really want this, but it's not critical to making
k8s "useful".

Pluggable authentication: Overlaps with the other identity topic.  Having one
topic seems clearer.

Pod spreading: We still want this, but it's not critical for 1.0.

Container status snippets: We still want this, but it's not critical for 1.0.

Docker-daemon-kills-all-children-on-exit problem: This is still a big problem,
but we're not going to gate our 1.0 on something we don't control.  This has
to be documented as a shortcoming in general.

Interconnection of services: expand / decompose the service pattern: overlaps
with the other services topic.

Recipes for settings where networking is not like GCE: This is happening in
the form of cloudprovider modules, but is not going to gate 1.0.