- load all histogrammable metrics on start, based on `{le!=''}` series
query
- select dropdown shows all those metrics as well as histograms in a
special group
- select a metric will write fill the metric in the query box
- if a histogram is chosen, it will write a complete
`histogram_quantile` query
- added new dependency: rc-cascader
- Clear All button to clear all queries and results
- moved result viewer buttons below query rows to make it more clear
that they govern result options
- position was determined by SPACE, but Prometheus selectors can
contain spaces
- added negative lookahead to check if space is outside a selector
- moved braces plugin into PromQueryField since braces are prom specific
- queries are saved to localstorage history array
- one history per datasource type (plugin ID)
- 100 items kept with timestamps
- history suggestions can be pulled up with Ctrl-SPACE
* Explore: facetting for label completion
- unified metric and non-metric label completion
- label keys and values are now fetched fresh for each valid selector
- complete selector means only values are suggested that are supported
by the selector
- properly implemented metric lookup for selectors (until the first
metric was used which breaks when multiple metrics are present)
- typeahead tests now need a valid selection to demark the cursor
* Fix facetting queries for empty selector
* Add click on explore table cell to add filter to query
- move query state from query row to explore container to be able to set
modified queries
- added TS interface for columns in table model
- plumbing from table cell click to datasource
- add modifyQuery to prometheus datasource
- implement addFilter as addLabelToQuery with tests
* Review feedback
- using airbnb style for Cell declaration
- fixed addLabelToQuery for complex label values
