Basic initial instrumentation of the apiserver

the "code" label from the latencies SummaryVec.

Allow proxying to a resource at /

Docker 1.4.1 on Fedora no longer provisions a docker group

Updated etcd-pod-dir-fetch logging.

prometheus library for monitoring, which exports some basic resource
usage metrics by default, like number of goroutines, open file
descriptors, resident and virtual memory, etc. I've also started adding
in request counters and latency histograms, but have only added them to two
of our HTTP handlers. If this looks reasonable, I'll add them to the rest
in a second PR.

Add restart to the kube apiserver.

Namespace as kind

Explicitly send error string to Fatal log 2

Port TestBasic & TestPrivate to Ginkgo

Add some error checking to prevent obscure failures.

Configurable API prefix for kubectl proxy

Fixes #4261

Add steps to the development guide for how to use godep to update an existing dependency

Add a simple driver to test cluster networking.

Explicitly send the error string to the Fatal log.

Add a label command to kubectl.

Support readiness checks

refactor pkg/probe ProbeRunners to interfaces and move global probers into kubelet field for testability

Update prometheus instrumentation library to include fix for building for linux/arm and linux/386 platforms

Fix vagrant networking round 2

Add a route for /proxy/<kind>/<name>/ without requiring additional path
information. This allows for e.g. /proxy/service/myservice/, which will
proxy to the service at /, instead of always requiring something in the
path.

Add example for using namespaces

existing dependency.

Also change from the numbered lists from markdown that didn't work due to
the intervening code blocks to just raw text numbered lists.

for linux/arm and linux/386 platforms.

Updated logging. If etcd-pod-dir-fetch fails because dir was absent, an info message is logged. 2) For all other reasons, the regular error message is logged.