Add continuous integrated testing using Travis CI and PlatformIO

[photodude]

Add continuous integrated testing using Travis CI and PlatformIO. Requires signing up for the free service details can be found in the docs

This is a low-level continuous integrated testing the ensures the library functions and PR's are valid. The low-level Testing verifies the library against the supplied example demo.ino

You can see the passing build with this link to my Travis CI branch which has been configured to test https://travis-ci.org/photodude/DualVNH5019MotorShieldMod3/builds/151091859

Currently, this only tests against 2 boards (uno and megaatmega2560) additional boards can be added for tested. (example with more boards https://travis-ci.org/photodude/DualVNH5019MotorShieldMod3/builds/151090810)

[ryantm]

Cool; thanks for the contribution!

[photodude]

You are welcome.

I've got an updated version that breaks the boards out individually and will allow failures for boards that support is in development for (or to just show that the boards don't work). See this example build https://travis-ci.org/photodude/DualVNH5019MotorShieldMod3/builds/151094125

If you want I can submit a new PR for that.

[ryantm]

Thanks. @DavidEGrayson simplified the .travis.yml file and broke out the boards: https://github.com/pololu/dual-vnh5019-motor-shield/blob/dd13365685a86eed2f75ecd667dd7467e797c298/.travis.yml

[photodude]

Those are some nice modifications and simplifications that @DavidEGrayson has made, I have incorporated those into my .travis.yml to make my version more portable for adding testing to my other projects.

[ryantm]

@photodude I mentioned you in the blog post I wrote about us using this in our Arduino libraries. By the way, we've updated the script on master to set some shell options so the script properly fails when the board compilations fail. Here is an example of the problem: https://travis-ci.org/pololu/balboa-32u4-arduino-library/builds/208827161

[photodude]

Thanks for the mention @ryantm glad the contribution was helpful. I'll definitely make that update for my scripts too.

Maybe someday actual unit testing of the arduino libraries can be added.

[photodude]

@ryantm one correction on the blog post spelling, my last name is Sorensen. Not a big deal, it's a common difference of e vs o. Again, thanks for the mention in the blog post.

[ryantm]

@photodude Sorry! We fixed it!