* merge master

* TimeSeries: datasources with labels should export tags (not labels) (#18977)

* merge master

* export prometheus tags

* Annotations: Add annotations support to Loki (#18949)

* Explore: Unify background color for fresh logs (#18973)

* Singlestat: render lines on the panel when sparklines are enabled (#18984)

* Image rendering: Add deprecation warning when PhantomJS is used for rendering images (#18933)

* Add deprecation warning

* Update pkg/services/rendering/rendering.go

Co-Authored-By: Marcus Efraimsson <marcus.efraimsson@gmail.com>

* Units: Adding T,P,E,Z,and Y bytes (#18706)

* Adding T and P for bytes

Luckily, all the hard work was done before; just added in these prefixes for our production environment.

* Future-proofing with other values (why not?)

* Yottaflops?

* Cutting back down to Peta sizes, except for hashes

* Refactor: move ScopedVars to grafana/data (#18992)

* Refactor: Move sql_engine to sub package of tsdb (#18991)

this way importing the tsdb package does not come with xorm dependencies

* use DataFrame in heatmaps

* actually use the setting :)

* remove unused timeSrv

* merge with master / useDataFrames

* fix test function

* merge master

* fix datasource type on snapshot

* reuse DataFrame calcs from graph panel

* update comments