add option to log reports to file or custom logTo function on cucumber

[sebsorin]

Add an option on cucumber framework to log reports to a file or a custom loTo function.
This is helpfull to write json reports in a file for use in jenkins (cucumber/cucumber-js#90).

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[sjelin]

Needs a test

[googlebot]

CLAs look good, thanks!

[sjelin]

I know we should have merged this in ages ago, but now we're moving cucumber support into a separate repo/npm module. Please send your pull request to https://github.com/mattfritz/protractor-cucumber-framework

[skovalyov]

@sjelin var cucumberFrameworkPath = require('protractor-cucumber-framework').resolve(); fails with TypeError: Object #<Object> has no method 'resolve'. Probably due to my Node v0.10.29. So I'm using https://github.com/substack/node-resolve for now.