Remove jshint pragmas, add global config - still passing

[sudodoki]

There might be an issue for developers who have jshint on by default in their editor (see this commit for example), and since there's no hard rules laid out in the project, we can add global variables & ability to pass on 'use strict' for now.

[sejoker]

I agree to come up with jshint's default settings for the project, although I would consider adding 'use strict' later.