Log Message:
Update ruby-tw to 0.4.2.

Changes from History.txt:

=== 0.4.2 2013-05-18

* enable -id=(id) option in pipe-tweet

=== 0.4.1 2013-05-18

* replty to status % tw "@shokai hello!" --id=1123454321

=== 0.4.0 2013-05-16

* status_id % tw --id
* RT tweet % tw --rt=12345136
* Fav tweet % tw --fav=12345136