message: do not let go behind 0 char
diff: @@ -377,8 +377,9 @@ export class Position extends vscode.Position {
  * breaks.
  */
  public getLeft(count: number = 1): Position {
  - if (!this.isLineBeginning()) {
  - return new Position(this.line, this.character - count);
  + let newCharacter = Math.max(this.character - count, 0);
  + if (newCharacter !== this.character) {
  + return new Position(this.line, newCharacter);
  }
  return this;
  