Enable Coverity-Scan API token in Travis

[nyanp]

This is continued from #531. This PR replaces dummy API token with encrypted token for coverity scan-build.

[mention-bot]

@nyanp, thanks for your PR! By analyzing the history of the files in this pull request, we identified @edgarriba, @Abai and @Randl to be potential reviewers.

[Randl]

I suppose to change notification email, and also branch. Master probably would mean checks are performed too often.

[nyanp]

@Randl It's up to you to change your notification settings :) Any suggestions to avoid interrupting our mailbox?

[Randl]

@nyanp Well there is that site, https://www.kill-the-newsletter.com/ , which converts emails to RSS. Not sure if appropriate, but might be worth trying

[edgarriba]

is there any way to show results in a badge? https://shields.io/

[Randl]

I don't think so

[edgarriba]

well I see this: https://img.shields.io/coverity/scan/3997.svg
however not sure which output gives

[nyanp]

Coverity allows us to submit 4 builds/day.
https://scan.coverity.com/faq#frequency

We might need to separate the coverity build to coverity_scan branch and invoke build by hand (as they recommend at https://scan.coverity.com/faq#frequency) in order to avoid build breaking due to the API restriction.

I met an another problem around TBB with clang (clang 3.5.0 couldn't find std::is_tribially_copyable in the latest version of TBB https://travis-ci.org/tiny-dnn/tiny-dnn/jobs/214276470), but it should be treated as an another issue. I'll investigate the problem tomorrow.

[bhack]

Keras removed coverity cause was not satisfied by the quality of the service.. probably clang static coverage is enough..

[nyanp]

@bhack
After struggling with that, I reached to the similar mind to Keras team... Anyway I think it's ok to keep coverity_scan branch as is and we should remove coverity API from master branch.

[nyanp]

@edgarriba

I think it's ok to keep coverity_scan branch as is and we should remove coverity API from master branch.

What do you think about removing the coverity build from master branch?

[edgarriba]

go ahead

[nyanp]

ok👌