divide test into env. specific folders

[jimmywarting]

...Makes it easier to run test file that are NodeJS or Browser specific and can't run in any other env.

/test
|-- nodejs           <-- NodeJS specific 
|   |-- test001.js   <-- fs test
|-- browsers         <-- browser specific 
|   |-- test002.js   <-- indexeddb test 
|   |-- test006.js   <-- localstorage test
|-- test003.js       <-- universal
|-- test004.js       <-- universal

After fixing this then we could perhaps remove the DOM-storage (aka local/session-storage) dependency and only have that running inside browser with proper CI/CD pipeline.