Add polkadot-js types

[joelamouche]

• add json files for the types in a the polkadot-js folder

tests having been modified because types are not used in master yet

solves MOON-128

[JoshOrndorff]

tests having been modified because types are not used in master yet

I don't understand this part. It seems the tests have not been modified, right?

We also should add some basic integration test. For example make sure tokens can be transferred and the events received via Polkadot JS

[crystalin]

I've started to write test using PolkadotJs and will use those files to setup the types correctly. That will allow us to verify they are valid

[JoshOrndorff]

Oh, I see. The tests that I saw the other day are not yet in master. So this PR can go in first, and then before @crystalin merges his tests, he'll update them to use these files.

That means we don't know whether the comments will be a problem, so I'd say remove them.

Final question: Why are there separate alphanet-types and parachain-types?

[crystalin]

@joelamouche please make those valid json file.
@JoshOrndorff I asked those 2 types because there might be differences between what we produce as a parachain and what we will produce for alphanet (and other networks). It might be too early to think about it however. @joelamouche can you remove the parachain types for now ?

[joelamouche]

done