message: Accept @ in command names for intellisense
  Related to
diff: @@ -372,7 +372,7 @@ export class Command {
  }
  private getCmdFromContent(file: string, content: string): Suggestion[] {
  - const cmdReg = /\\([a-zA-Z]+)({[^{}]*})?({[^{}]*})?({[^{}]*})?/g
  + const cmdReg = /\\([a-zA-Z@]+)({[^{}]*})?({[^{}]*})?({[^{}]*})?/g
  const cmds: Suggestion[] = []
  const cmdList: string[] = []
  while (true) {
  