Add option --script-language to explicitly set javascript or coffeescript

https://github.com/ariya/phantomjs/issues/11744
Reject script-language values other than javascript and coffeescript

https://github.com/ariya/phantomjs/issues/11744
Select monospace font family properly.

CSS style "font-family: monospace" should select monospace font.

https://github.com/ariya/phantomjs/issues/11764
Merge branch 'master' into r3b-flash