tour: use better wording to explain run/format keyboard shortcuts

Fixes golang/tour#526

Change-Id: I2338cf6d06dd8756dcb81a88453558c5b2de2257
Reviewed-on: https://go-review.googlesource.com/122097
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>

content/welcome.article

@@ -25,7 +25,7 @@ You can navigate through them using
 
 The tour is interactive. Click the
 [[javascript:highlightAndClick("#run")][Run]] button now
-(or type `shift-enter`) to compile and run the program on
+(or press `Shift` + `Enter`) to compile and run the program on
 #appengine: a remote server.
 your computer.
 The result is displayed below the code.
@@ -34,8 +34,8 @@ These example programs demonstrate different aspects of Go. The programs in the
 
 Edit the program and run it again.
 
-Note that when you click on [[javascript:highlightAndClick("#format")][Format]] or `ctrl-enter`
-the text in the editor is formatted using the
+When you click on [[javascript:highlightAndClick("#format")][Format]]
+(shortcut: `Ctrl` + `Enter`), the text in the editor is formatted using the
 [[https://golang.org/cmd/gofmt/][gofmt]] tool. You can switch syntax highlighting on and off
 by clicking on the [[javascript:highlightAndClick(".syntax-checkbox")][syntax]] button.