With perl 5.6.0, GetOpt::Std is functional, use it.

With perl 5.6.0, GetOpt::Std is functional, use it.
Add -p (prick) and -t (test) option.
reword error handling as follows:
makewhatis tries harder to find section and/or subject lines in man pages,
even when the formatting is slightly incorrect.
-p mode diagnoses problems.
-t can be used to quickly test a new man page.
Approved by millert@.  aaron@ would like `The options are as follows...'
style, but:
- I don't think this would be as clear,
- he hasn't come up with actual replacement text yet...

At least this is accurate documentation.