Add missing Test dependency

[maedjyuk-ghoti]

Added junit dependency

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[maedjyuk-ghoti]

I signed it!

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CLAs look good, thanks!

[ghost]

Normally it should be testCompile, but as long as there would be only Android instrumentation tests (androidTest package), using androidTestCompile is enough.
And yes, this repo is missing Junit dependency :-)

[slinzner]

LGTM

[dazza5000]

merge conflict