Add Web project to examples/playground

[roperzh]

The playground example is meant to be used to iterate the stdlib, but currently only has an iOS example project.

We need to do something similar to what has already been done for the other example projects, places to look at:

• examples/lorem-ipsum
• examples/playground

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.