Update tutorials to ignore test-harness generated output files

[bbejeck]

Update the project to ignore the following:

1. All output directories in the tutorials

[bbejeck]

@ybyzek WDYT?

If you agree I'll get started on a PR for this or whoever wants to pick this up.

[ybyzek]

@bbejeck I'm a Gradle noob but this makes sense to me. (also discussed in #752)

[gAmUssA]

@bbejeck dont ignore bat (people on windows won't be able to use Gradle wrapper), and Gradle.jar (wrapper will stop working)

[bbejeck]

dont ignore bat (people on windows won't be able to use Gradle wrapper), and Gradle.jar (wrapper will stop working)

@gAmUssA ack. I did find in the gradle docs that gradle wrapper and associate jar file are expected to be included in source control.

\cc @ybyzek