Document best practices for where to put the jsconfig.json/tsconfig.json

[egamma]

We lack guidance for where to put jsconfig.json file. Users sometimes have more than one project context inside a workspace, putting the jsconfig.json at the root results in adding all the files into a single project context. This can be both inefficient and result in unwanted completions suggestions for Intellisense.

The recommendation is to have a jsconfig.json at the root of each project inside your workspace. If the project has a src folder than this is the root and this is where the jsconfig.json should be put.

[egamma]

I made a PR #121 with some additional tips on the jsconfig setup.