6 CLs

Adding example for deffixtype.

Improving working-with-packages topic to disambiguate the confusion I had back in July. Thanks to Sol for providing the clarification.

Making the three required arguments of deffixtype really required by adding a guard that their 'and' be non-nil.  I thought about doing something fancier, but I didn't want to think about what might happen if a call to er occurred.  Presumably these all happen at the top-level, but I don't know.

Adding a convention suffix of '-limit' to best-practices

Adding an introduction to GL inside the Best Practices topic area.



It shows a merge in the pull request commit list, so I guess we'll see whether it reportedly touches more than the two files I've modified.