Add CatAge project
Main: Build basic layout
Bind catAgeField to code
Bind humanAgeField to code
Bind calculate button action to code
ViewController: Add catAgeToHumanAge
Calculate cat age as human age
Remove calculate button
Calculate cat age as human age on editing changed
Validate cat age input
Validate length of input for cat age
Hide keyboard on tapped background
Merge remote-tracking branch 'origin/cat-age'