content: add newline to imports.go Printf call

Fixes golang/tour#615

Change-Id: I59401792b7aeddbdbf4baadeb822827bd19835cf
Reviewed-on: https://go-review.googlesource.com/138615
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/content/basics/imports.go b/content/basics/imports.go
index 9854405..8424aca 100644
--- a/content/basics/imports.go
+++ b/content/basics/imports.go
@@ -8,5 +8,5 @@
 )
 
 func main() {
-	fmt.Printf("Now you have %g problems.", math.Sqrt(7))
+	fmt.Printf("Now you have %g problems.\n", math.Sqrt(7))
 }