Support for build info on service tunnels

[seriema]

The DigDug docs mention:

buildId | number | The build number of the software being tested by the job. Supported by Sauce Labs. https://theintern.github.io/digdug/global.html

The BrowserStack docs mention:

build | Allows the user to specify a name for a logical group of tests. | Example: build 4.5 | Default: Untitled Build https://www.browserstack.com/automate/capabilities#capabilities-browserstack

It'd be pretty nifty with support for buildId on BrowserStack. I hacked it into the environments config just to try it out, and it looks pretty good:

The config I used:

{ browserName: "chrome", os: "WINDOWS", os_version: "10", name: "example session name", build: 3186 }

[jason0x43]

At least SauceLabs, BrowserStack, and CrossBrowserTesting support some level of test description;

• CBT accepts a build name (doc)
• BS accepts a name for a single test run, a build for a group of tests, and a project for a group of builds (doc)
• SL accepts a build name, tags, and also allows arbitrary custom data (doc)