[NOTICE] Breaking change in tajo.sh and tajo-env.sh

[Hyunsik Choi]

Hi folks,

In TAJO-991, tajo.sh and tajo-env.sh sets some default values. Without
the default values, TajoWorker will not work correctly.

So, you should update the files if you are using master branch in Git.

Thanks,
Hyunsik