webfsd Port

Hi,

This is my first port and I have tried my best to follow the guide and man pages, but still have a few questions.

Security Recommendations Bullet 2 "Any software to be…": Is there a recommended tool to scan for these buffer overflow problems?

I was trying to use MANPREFIX but only get an empty string with `make show=MANPREFIX`. Is this normal?

When running `/usr/ports/infrastructure/bin/portcheck` I get the following warning:
```
manual pages should go under ${PREFIX}/man/ rather than under ${PREFIX}/share/man/
```
I tried using `MAKE_FLAGS` and `Fake_FLAGS` to change set the variable `mandir` in package's GNUmakefile to fix this but portcheck still gives this warning.

Also, a helpful improvement to the guide in Instruction 9 Section 3 would be to mention `post-install` and `${INSTALL_MAN}`.

Thanks for the help.