Make 'utils' executable

They weren't due to me previously having stored the entire project on an external NTFS harddrive,
which obviously didn't support Linux's permissions system, but instead treated every file as
having 755 permissions.

It is fixed now. :)
Update 'generate-asdoc' to allow for a 'lib' folder

Realized this was required when I tried to generate the documentation
for [Flixel Power Tools](https://github.com/FlixelCommunity/Flixel-
Power-Tools/).
Fix `utils`

Changed permissions to 755
The `generate-asdoc.sh` script now allows for a `lib` folder.