skyline.analyzer.metrics

Added functionality to analyzer.py for skyline to feed all of its own metrics
back to graphite.  This results in skyline analyzing its own metrics for free :)
The resultant graphite metrics and carbon files (if using whisper and not ceres)
that this provides are (e.g):
skyline/
├── analyzer
│   ├── anomaly_breakdown
│   │   ├── first_hour_average.wsp
│   │   ├── grubbs.wsp
│   │   ├── histogram_bins.wsp
│   │   ├── ks_test.wsp
│   │   ├── least_squares.wsp
│   │   ├── mean_subtraction_cumulation.wsp
│   │   ├── median_absolute_deviation.wsp
│   │   ├── stddev_from_average.wsp
│   │   └── stddev_from_moving_average.wsp
│   ├── duration.wsp
│   ├── exceptions
│   │   ├── Boring.wsp
│   │   └── Stale.wsp
│   ├── projected.wsp
│   ├── run_time.wsp
│   ├── total_analyzed.wsp
│   ├── total_anomalies.wsp
│   └── total_metrics.wsp
└── horizon
    └── queue_size.wsp
There will be more for other exceptions and any further added algorithms, this
is however quite trivial in terms of whisper storage and new metrics adds.
Modified:
src/analyzer/analyzer.py