Squashed 'typescript-contacts-demo/' content from commit 4a1c6a2

git-subtree-dir: typescript-contacts-demo
git-subtree-split: 4a1c6a205c606fd6320f32b3050c5e27399d6d40
Merge commit '18526c8548988d51402f87ec9e1507bfc2360bc3' as 'typescript-contacts-demo'
Adding gitignore