travis "before script" should only be run once

[boneskull]

This script basically asserts define doesn't appear in the browser distfile (mocha.js).

• This check probably needs to have its own line in the build matrix
• It should be invoked via a script in package-scripts.js so developers can run it locally

[vkarpov15]

@boneskull I'm not sure which script you're talking about, can you clarify?

[boneskull]

scripts/travis-before-script.sh

[Bamieh]

I'll check it out later on today
@outsideris wants to work on it

[outsideris]

@Bamieh Oops. I'm trying to fix it. Can I submit for PR for this?

[outsideris]

I worried about you are working on it.

[Bamieh]

@outsideris thanks for helping out!