Add per graph auto-refresh option to web UI.

This adds a drop-down menu to select/disable a auto-refresh interval.
Register pprof /debug endpoints with custom HTTP mux.
Extract dto.SampleValueSeries into model.Values.
Merge pull request #171 from prometheus/julius-fix-debug

Register pprof /debug endpoints with custom HTTP mux.
Merge pull request #170 from prometheus/refactor/readability/business-logic-types

Extract dto.SampleValueSeries into model.Values.
Merge pull request #158 from prometheus/feature/auto-refresh

Add per graph auto-refresh option to web UI.
Implement initial no-op alert parsing and rule parsing tests.
Merge pull request #174 from prometheus/julius-alerting

Implement initial no-op alert parsing and rule parsing tests.
Convert the TestInstant value into UTC.

For the forthcoming Curator, we don't record timezone information in
the samples, nor do we in the curation remarks.  All times are
recorded UTC.  That said, for the test environment to better match
production, the special instant should be in UTC.
Merge pull request #175 from prometheus/refactor/tests/affix-timezone

Convert the TestInstant value into UTC.
WIP - Truncate irrelevant chunk values.

This does not work with the view tests.
Convert time readers to represent time in UTC.

Go's time.Time represents time as UTC in its fundamental data type.
That said, when using ``time.Unix(...)``, it sets the zone for the
time representation to the local.  Unfortunately with diagnosis and
our tests, it is a PITA to jump between various zones, even though
the serialized version remains the same.

To keep things easy, all places where times are generated or read
are converted into UTC.  These conversions are cheap, for
``Time.In`` merely changes a pointer reference in the struct,
nothing more.  This enables me to diagnose test failures with fixture
data very easily.
Merge pull request #177 from prometheus/refactor/time/everything-in-utc

Convert time readers to represent time in UTC.
Fixes/cleanups to renderView() samples truncation.
Merge pull request #176 from prometheus/optimization/view-materialization/slice-chunking

Truncate irrelevant chunk values.
Include generated Protocol Buffer descriptor.

The Protocol Buffer compiler supports generating a machine-readable
descriptor file encoded as a provided Protocol Buffer message type,
which can be used to decode messages that have been encoded with it
after-the-fact.  The generated descriptor also bundles in dependent
message types.

We can use this to perform forensics on old Prometheus clients, if
necessary.
Move protobuf descriptor and add content-type.

- move to static/generated
- set content-type based on extension '.description'
Merge pull request #179 from prometheus/feature/protocol-buffer-descriptor-inclusion

Include generated Protocol Buffer descriptor.
Add instance label to health (up) timeseries.
Capture build information and print with -version