Need to pass '--allow-file-access-from-files' down to puppeteer launch args.

[g2nconnell]

Running jasmine as part of our grunt build, headless chrome requires the argument "--allow-file-access-from-files". This is because require tries to fetch dependencies using "file://" protocol.
Need to be able to specify this option in the grunt file and have it passed to puppeteer's launch options.

I believe this part of the reason for other user's issue of specs not running.

[steveoh]

Interesting. Up for adding a pr? We run a server and require files that way so I am not motivated to add that.

[vatsala-glory]

created the PR #306