New Feature: Head Comments

[TonyYu123]

As Competitive Companion can pass the info of the problem, a head comment can be attached on the begining of the file generated to make the problem clearer. Example:

// Problem: Range Xor Queries
// Contest: CSES - CSES Problem Set
// URL: https://cses.fi/problemset/task/1650
// Memory Limit: 512 MB
// Time Limit: 1000 ms

It is achieved in this project: cpeditor