BREAKING CHANGES

Requests for improvements:

• Request for improvements Buy Robonomics Subscription for Another account #376
• Request for Improvements Subscription Prolongation #377

Proposed solution plan:

Implementation requested improvements while backward compatibility brings exceed complexity and code hacks. To keep sources simple and safe breaking changes are introduced, keep aware.

• New subscription is inactive by default.
• Subscription activation required by call claim extrinsic.
• During activation additional parameter can be added for activation on other account.
• Activation method automatically adds owner account into device list.
• Change subscription_id type to u64.
• Subscription ledger splits in two different storages: subscription kind ledger and subscription owner ledger.
• Add storage migration required and will be processed during runtime upgrade.

Some cleanups:

• Remove oracles.
• Remove set_subscription and set_oracle extrinsics.