Support creating referenda from Inline preimage

[ggwpez]

• I'm submitting a ...

• Bug report
• Feature request
• Support request
• Other

• What is the current behavior and expected behavior?

PJS currently forces the user to put a preimage hash when submitting a referendum.

It does not offer the option to use Inline bounded calls. These can be up to 128 encoded data and do not need to go through the preimages pallet.
This removes a whole class of errors of users entering wrong preimage hashes or lengths.

It is present in the extrinsics tab, as can be seen here:

• What is the motivation for changing the behavior?

Ref 514 that was jinxed because of wrong preimage len when the preimage was just 46 byte.

• Please tell us about your environment:

• Version:

• Environment:

  • Node.js
  • Browser
  • Other (limited support for other environments)

• Language:

  • JavaScript
  • TypeScript (include tsc --version)
  • Other