* do not spawn additional task for on-demand relays

* compilation

* prefix in relay loops logs

* fmt

* complex headers+messages relay

* post-merge fix

* fix + test issue with on-demand not starting

* administrative metrics

* fmt

* fix compilation

* fix compilation again

* and another one

* remove GenericLoopMetrics

* chttp -> isahc

* remove redundant marker

* not about price metrics

* fmt

* Update copyright date to 2021

* Bump date in license header template

* Fix SS58 formatting of addresses.

* cargo fmt --all

* Use only lifetime hint.

* Update relays/bin-substrate/src/cli.rs

Co-authored-by: Hernando Castano <[email protected]>

* Remove unnecessary optimisation.

* Add re-formatting test.

* cargo fmt --all

Co-authored-by: Hernando Castano <[email protected]>

* slightly changed relay loop initialization

* git mv

* clippy

* more clippy

* loop_run -> run_loop

* review and clippy

* clippy

* Remove chains.

* Move relay clients.

* Flatten generic.

* Fix fmt.

* Nest some crates.

* Alter command execution to make it easier to add new bridges.

* Rename sub-dirs.

* cargo fmt --all

* Address clippy.

* Update relays/substrate/src/rialto_millau/cli.rs

Co-authored-by: Hernando Castano <[email protected]>

Co-authored-by: Hernando Castano <[email protected]>

* extract common parts of relay loops: begin

* merge client impls

* backoff in exchange loop

* reconnect without clone

* fixed clippy warnings

* Revert "Actually use pinned nightly version when building runtimes (#465)"

This reverts commit 03ef7638.

* Revert "Pin Rust Nightly Version (#420)"

This reverts commit 8902ac20.

* fix after revert

* another fix after revert

* more clippy fixes

* Fix cargo-deny.

* Update time crate.

* Fix time issues.

* extracted relay crates

* moved metrics to utils

* exchange-relay compilation

* fix compilation of headers-relay

* fixed messages-relay compilation

* fixed ethereum-poa-relay compilation

* cargo lock

* cargo fmt --all

* clippy

* cargo fmt --all

* fix tests compilation

* clippy

* eof

* module level docs

* removed obsolete comment

* #![warn(missing_docs)]

* .0 -> Deref

* post-merge fix

* cargo fmt

* Update relays/headers-relay/src/headers.rs

Co-authored-by: Hernando Castano <[email protected]>

* Update relays/headers-relay/src/headers.rs

Co-authored-by: Hernando Castano <[email protected]>

* Update relays/headers-relay/src/lib.rs

Co-authored-by: Hernando Castano <[email protected]>

Co-authored-by: Hernando Castano <[email protected]>