Fix error in example

Remove confuse import in clockface test (quii#606)

In first code demo, it import "github.com/gypsydave5/learn-go-with-tests/math/v1/clockface". But learner need create clockface.go by themself and that import cause confusing

little edits

mention GOOS

Update maps.md (quii#588)

Change order here to match order shown in previous snippet of this test.

lets not do closures on chapter 1

bad copy and paste

add new generics chapter to toc

remove some past-tense-ness

just comment out everything until it works