Use module.exports syntax in util files

[s1na]

I remember facing some issues with the ES6 export syntax and it revolved around browsers. I suggest we use module.exports for now like the rest of the library. We can go back to the cleaner export syntax during the Typescript migration.

[holgerd77]

Hmm, builds didn't run through, restarted both.

[s1na]

Seems like a problem with fetching nodejs to prepare the environment:

curl: (7) Failed to connect to nodejs.org port 443: Connection timed out

[coveralls]

Coverage increased (+0.4%) to 94.176% when pulling 247fb86 on utils-export-syntax into cf40000 on master.

[s1na]

Restarted the tasks (yet again) and now they pass