* adds `npm start` / `yarn start` script
* starts a webpack-dev-server using the dev config, served on :3333
* hot reloading (HMR) for react/styles, not working for angular code
* new entry `dev.ts` for dynamic imports of CSS theme (ExtractText does
not work with HMR)
* TS loader pipeline moved out of common to add HMR for react
* applied `hot()` to some react containers (that's their new default
 export, named exports remains for testing)
* added sections to README
* updated yarn.lock

[skip ci]

[skip ci]

* report active users in graphite stats

* use bus to publish system stats

* metrics: avoid using events unless we have to

this commit also changes the default interval
for updating the stats gauges. Seems like the old values
was a product of previous metrics implementation

[skip ci]

* fix: Row state is now ignored when looking for dashboawrd changes, had to fix bug in expand logic to make fix work. Also moved the ChangeTracker to it's own file and moved tests to jest, fixes #11208

* removed commented out log calls

improved ux for permission list

ux: sizing and positioning of dashboard settings menu icons

Revert "build: remove code cov"

Revert "removes codecov from frontend tests"

fix unconvert issues

bra should use the proper build script

In addition to closing #11578

[skip ci]

tsdb: improve $__timeFilter macro for postgres

* migrated dropdown-typeahead to ts

* removed console.logs

* added @ngInject

ordered user orgs alphabeticaly 

Support deleting empty playlist

Show Grafana version and build in Help menu

* `bra run` is used during development, but it was not using build.go
which sets a couple of globals, e.g., the commit (currently set to "NA")
* This will help in reporting the commit that someone is basing their
screenshot on.