* fix light client startup

* fix grumbles

* Revert "Pruning changes trie without digests (#952)"

This reverts commit 468d4698.

* pruning changes tries without digests

* u64::max_value()

* Update wasm files and fix merge conflict

* Fixes tests

* pruning changes tries without digests

* u64::max_value()

Co-Authored-By: rphmeier <[email protected]>

Co-Authored-By: rphmeier <[email protected]>

Co-Authored-By: rphmeier <[email protected]>

Co-Authored-By: rphmeier <[email protected]>

Co-Authored-By: rphmeier <[email protected]>

* Update wasmi to 0.4.2

* Add simple benchmarks.

This makes it possible to support `GenesisConfig`s that to do not use
generic parameter.

* Make sure to call the runtime trait functions

The runtime trait functions export their functions as extern c
functions. These functions itself call the trait functions. This commit
makes sure that the trait functions are called and not functions with
the same name that are implemented for the runtime.

* Update the wasm files

* add extra verification for aura

* fix tests

* adjust documentation wording

* Revert "start to refactor block import wrapper a bit"

This reverts commit b919de49.

* Refactor grandpa stuff to get tests almost compiling

* Fixes after rebase

* Fixes merge compile errors

* build CHT for changes tries roots

* collect chnages tries roots proof in key_changes_proof

* flush check_changes_proof

* fixed compilation

* LightDataChecker now has a ref to the blockchain

* continue passing proofs

* new light db tests

* more CHT tests

* more tests for key changes proof when headers are missing

* lost files