Update add panel flow

Clicking outside TimePicker (Angular & React versions) should close it

Changes default interpolation for Stackdriver filter to be regex. Fixes #15182

For the filter expression, a better default is to
interpolate multi variables as a regex rather than
the default globbing pattern.

Also, uses the real TemplateSrv class rather than
stubbing it in the tests.

Handle onPaste because of bug in this Slate version

docs: fixes #14940

Added custom scrollbar and remember scroll pos to jump back to same scroll pos when going back to dashboard from edit mode

Better stackdriver logo (bigger + svg)