Jenkins: Switch to email-ext plugin for build-email notifications (#2893)
Jenkins: Switch to email-ext plugin for build-email notifications (#2893)

...and also include failed test results.

edmorley/treeherder,KWierso/treeherder,edmorley/treeherder,edmorley/treeherder,KWierso/treeherder,KWierso/treeherder,edmorley/treeherder,KWierso/treeherder