add sidechain calls
also, dropped pinned revisions for substrate. use this to fix deps:
cargo update -p sp-std --precise 743accbe3256de2fc615adcaa3ab03ebdbbb4dbd
also, dropped pinned revisions for substrate. use this to fix deps:
cargo update -p sp-std --precise 743accbe3256de2fc615adcaa3ab03ebdbbb4dbd