Move Storage Parser from Bridge Pallet (#793)

* Move storage proof checker to runtime primtives

* Add method for parsing storage proofs

* Use finality-verifier pallet in runtime-common

* Get bridge pallet compiling again

* Use storage prover from bp-runtime in a few more places

* Don't leak `std` items from proof helper into `no-std` builds

* Fix benchmarking compilation

* Remove unused import in fuzzer