code: function(url, branch) {
    this.url = url;
    if (url.startsWith('https://api.github.com/repos/')) {
      this.path = url.substring(29);
      this.apiUrl = url;
    }
    else if (url.startsWith('https://github.com/')) {
      this.path = url.substring(19);
      this.apiUrl = 'https://api.github.com/repos/' + this.path;
    }
    else {
      throw new Error('Unsupported URL format: ' + url);
    }
    
    this.branch = branch ? branch : 'master';
    
    if (typeof window === 'undefined') {
      this.request = require('request');
      this.requestOptions = {headers: {'User-Agent': 'limberest'}};
    } 
    else {
      this.request = require('browser-request');
      this.requestOptions = {};
    }
  }
docs: github ui url https://github.com/limberest/limberest-demo OR... github api contents https://api.github.com/repos/limberest/limberest-demo