feat: add inline namespace for global helpers

[nolde]

Resolves #57

All tests are passing.

[davidmeirlevy]

Looks great.
Can you add more tests that will cover the new API you added?

[nolde]

Sure!

You had tests for map, store+map, and store+namespace+map (the ones using createNamespacedHelpers), so those should still be covered by the existing ones.

I will add some more for namespace+map, which are the only ones missing.

[nolde]

Done!

[nolde]

Anything else you need from me on this one, @davidmeirlevy ?

[davidmeirlevy]

@nolde nothing, that's awesome!
I'll publish the new version today.

also, if you can add this ability into the cloned branch of the #55 branch, that will be awesome too (this branch is having this package working for vue3).

[nolde]

Sure,, will take a look at that!

Might take a while longer though, with holidays coming up.

Thanks for merging!