Protobuf Duration value viewing and editing in JSON

The Google Protobuf Duration message value gets serialized to JSON as a string showing number of seconds. This is not readable, nor editable.

This extension shows a decoration next to the "123s" value.

A link in the hover invokes a user friendly way of editing the value in days/hours/minutes/seconds.

Debugging the extension

• npm install to initialize the project
• npm run watch to start the compiler in watch mode
• open this folder in VS Code and press F5
• this will open the [Extension Development Host] window, running the extension:
  • Open the sample1.json in the editor