Add ability to find accepted solutions in different languages

[vstrimaitis]

It would be cool to be able to find correct solutions to GCJ problems in a specific programming language. For example, my primary language might be X (or I'm currently trying to learn this language), but most of the solutions are in C++ - how do I find solutions, which are written in the language X? Currently there is no way to do that.

[chinesedfan]

FYI. I have created a Node.js script in my fork's branch, because I am good at Javascript than Python.

See https://github.com/chinesedfan/google_codejam_stats/blob/langs/scripts/attempts.js.