Support all versions of Puppeteer

[nesk]

Currently, PuPHPeteer locks the minor version used for Puppeteer because its exports aren't applying semver (see #22) and can change between releases.

Once the exports are no longer an issue, the version lock could be done on the major number instead of the minor one, this would allow users to install the latest version of Puppeteer or even an old one.

Notes:

• Edit the Travis matrix to test Puppeteer v1.0 and the latest 1.X version.
• Log Puppeteer's version.

[spekulatius]

I'd get onto this after adding support for the latest version #71.