message: show the chktex code in the diagnosticS
diff: @@ -163,6 +163,7 @@ export class Parser {
  const range = new vscode.Range(new vscode.Position(item.line - 1, item.position - 1),
  new vscode.Position(item.line - 1, item.position - 1))
  const diag = new vscode.Diagnostic(range, item.text, diagnostic_severity[item.type])
  + diag.code = item.code
  if (diagsCollection[item.file] === undefined) {
  diagsCollection[item.file] = []
  }
  