feature #199 Add emulator option to BrowserStack capabilities. (gries)

This PR was merged into the 2.0.x-dev branch.

Discussion
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Add emulator option to BrowserStack capabilities.

Hi,
I would like to add the emulator option to BrowserStack capabilities.

This option allows you to run iOS devices via. an Emulator instead of real devices which is sometimes necessary as they are using Appium to run tests on real devices, which fails for example if you try to delete cookies.
This option is currently not documented on BrowserStack but I got the hint of their support to use this option.

thank you

Commits
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a15cff9 Add emulator option to BrowserStack capabilities.

src/Behat/MinkExtension/ServiceContainer/Driver/BrowserStackFactory.php

@@ -61,6 +61,7 @@ class BrowserStackFactory extends Selenium2Factory
                 ->scalarNode('device')->end()
                 ->booleanNode('browserstack-debug')->end()
                 ->booleanNode('browserstack-tunnel')->end()
+                ->booleanNode('emulator')->end()
             ->end()
         ;