Adding filter bar support to Dashboard and Visualize

- Closes #1526 and Closes #538
- Adding fitler bar to Dashboard
- Addign filter bar to Visualize
- Adding click and brush handler to filter_bar component
- Adding tests for all the things
- Adding brush events to all apps
- Consolidate all filter addition code to filter bar
- Add donut option to pie visualization
- Adding AggConfigResult to hierarchical data
- Adding picker for multiple filter items
- Moved apply, disabled, negate to $$meta
- Removed $$hashKey from fitlers (part of the input box apply)
Moving 26427meta to meta and 26427indexPattern to meta.index
Moving $$meta to meta
Remove angular private vars from rison encoded strings
Adding test to make sure toRISON removes 50847prefixed vars
Merge pull request #2120 from simianhacker/filter_bar_beta_3

Adding filter bar support to Dashboard and Visualize