* remove substrate compat
* add hacky example
* simplify substrate-compat example
* simplify substrate-compat example
* cargo fmt
* fix build
* add more examples
* fix nit
* fix test build
* Update subxt/examples/substrate_compat_signer.rs
Co-authored-by: James Wilson <james@jsdw.me>
* keep only polkadot signer example
* remove more substrate compat related stuff
* fix example
* link to substrate signer example in book
* Update subxt/src/book/usage/transactions.rs
* Update subxt/src/book/usage/transactions.rs
* address grumbles
* fix nits
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Co-authored-by: James Wilson <james@jsdw.me>
Niklas Adolfsson