Get better format for long lines with PrettyTable

Based on current implement, the cli output format will be bad if
the lines are too long. This issue can be fixed by setting 'max_width'.
However, there is a bug against it, see
https://code.google.com/p/prettytable/source/browse/trunk/CHANGELOG?r=85
line 3. So the requirements.txt is updated as well.

docImpact
Fixes bug 1251283

Change-Id: I0d4192ad9d10a3d6d47a8319463a5edb57719a68