Integrates v8js into studionone/nginx-php7 image.

v8js extension is compiled and shared both to cli and fpm channels. To example code exists at this stage to demonstrate usage, however you should be able to follow examples at https://github.com/phpv8/v8js

Running phpinfo will show several extension parameters that are worth reviewing.

Docker image is available through docker hub at https://hub.docker.com/r/studionone/nginx-php7-v8js/