* test dart 1x in drone

* update dart image

* trigger build failure

* Revert "trigger build failure"

This reverts commit d565f348.

* add dart 2 test

* update build runner version

* test dart2

* only test dart jaguar

* remove pubspec.lock

* better wording

* use pub run test

* revert changes in build_runner

* update test in pom.xml

* update samples

* add dart scripts to ensure up-to-date