[tableVis] allow displaying partial rows, fixes #1911
Metric Vis
Create the metric visualization, which is a simple visualization that shows in large text the calculation of a metric.

Closes #1666.
Fix index pattern search error
Closes issue #1899.

When using the index name search, if you type quickly, then the search is not invoked after you have finished typing. This is because we had specified options to lodash debounce (https://lodash.com/docs#debounce) to execute the search function on the leading edge of the specified timeout, instead of the trailing edge (which it does by default). This change removes the overrides and fixes the issue.
remove console logging
[vis] use the isHierarchical method, not the property of the visType
[tableVis] allow configuring the way metrics are calculated for the metric vis
[aggResponse/tabify] allow overriding partialRows for hierarchical vis types
[aggResponse/tabify] tests to support 227d6fa
[tableVis] tests!
Make changes as per Spencer's suggestions
[aggConfig] allow mutliple metrics to be written in the DSL
[aggConfig] added test to prove 1ae3713
[tabify] write metrics for partial & hierarchical rows
[tableVis] modify the params to allow partial rows with metrics
[tabify] add tests to prove 261e804
[tabify] only place metrics on partial rows if we are not showing all metrics
[tabify] only remove metric columns for splits if we are using expanded metrics
[tabify] added tests to proved 2fcfceb and 9fea632
[tabify] added notes about what the differnt writer flags do
Merge pull request #1928 from lukasolson/metric-vis

Metric Visualization