whole_func_string: function(filename) {
        return new Promise((resolve, reject) => {
          fs.unlink(filename, function(err) {
            if (err && err.code != "ENOENT") {
              reject(err);
            } else {
              resolve(); 
            }
          });
        });
      }
func_code_string: function(filename) {
        return new Promise((resolve, reject) => {
          fs.unlink(filename, function(err) {
            if (err && err.code != "ENOENT") {
              reject(err);
            } else {
              resolve(); 
            }
          });
        });
      }
func_documentation_string: Deletes a file, does nothing if the file does not exist
  
  @param filename {String} file to delete
  @async