fixes #1419 implement failed tests count in summary output

[Mifrill]

closes #1419

[Mifrill]

locally the all tests passed with the integration tests, probably it's something not related to the current code changes

npm run integration
echo $?
=> 0

[johanneswuerbach]

@Mifrill could you rebase your branch? The tests are fixed in the latest master.

[Mifrill]

is it better to probably use the same approach as for TapReporter?:

// testem/lib/reporters/tap_reporter.js
summaryDisplay() {
    let lines = [
      `1..${  this.total}`,
      `# tests ${  this.total}`,
      `# pass  ${  this.pass}`,
      `# skip  ${  this.skipped}`,
      `# fail  ${  this.total - this.pass - this.skipped}`
    ];

    if (this.pass + this.skipped === this.total) {
      lines.push('');
      lines.push('# ok');
    }

    return lines.join('\n');
  }

[johanneswuerbach]

Yes, if you could do this change, it would probably be better to keep them consistent.

[Mifrill]

@johanneswuerbach thank you!

[johanneswuerbach]

Released as https://github.com/testem/testem/releases/tag/v3.3.0, thank you 👏