Organized stylebook into guidelines with reference numbers.

Considering this image, there are several tools enabled that shouldn't be, but for different reasons.

It would be nice to create issues in the tracker and reference these problems while being able to say what's wrong without reinventing the wheel every time. For example, the issue creator should be able to say;
"The Draft 'manage layers' button is enabled when it shouldn't be per guideline XXX.YYY.Z"
or
"The link tool group is improperly enabled per guideline XXX.YYY.X"


Whichever number scheme is used should allow the handbook to be reorganized in the future. large pages may be split into smaller ones.