Updating devel/p5-IO-Prompt from 0.99.4 to 0.99.7

pkgsrc changes:
- Add license definition

Upstream changes:
0.997  Sat Jan 30 07:17:07 2010
    - Removed another spurious warning for undefined inputs

0.996  Sun Jan 10 20:20:24 2010
    - Added dependency check and FAQ entry for /dev/tty (thanks Miller)
    - Removed spurious warning for undefined inputs
    - Changed versioning system

(sno)