Make it easier to use helper with async/await style programming

[myplacedk]

To do based on comments from here:

• Change code style / commit style
• Documentation. I documented the API and added example files. I feel like duplicating all relevant examples in the README with async versions is too noisy. Maybe all that needs is one or two references to the new example files, to make it more discoverable.
• Any other tasks. I'm just dipping my toes into Node Red, feedback is very welcome.

[jsf-clabot]

All committers have signed the CLA.

[myplacedk]

The CLA is now signed.

[myplacedk]

I used the wrong email address in the commits, sorry. I amended all the commits and force-pushed.

[JbIPS]

Woah thank you @myplacedk, I was trying to achieve the same thing!

I know it's a bit old, but is it still valid? @knolleary, is it mergeable? I can take care of the conflicts if necessary

[amir-arad]

@myplacedk Thank you! I hope this will be merged soon