
Changes between the last and this version:

v1.14:
  * tests from BigInt v1.70
  * we are compatible with API form BigInt v1.70
  * _rsft() and _lsft() modify their argument instead of making a copy,
    meaning brsft() and blsft() got about 20% faster in BigInt
  * added a working _zeros() method
  * added a working _log_int() method

