[+] chain_id field for tx_token. Now its universal and could be used not only for emission but for shard<->shard ledgers connections

[-] Removed cache init calls
[*] Splitted token byt tx_item_token, token itself and token_emission

and sign items.
Added auxiliary functions for working with transaction items

[+] Datum now inherits from dap_chain_t
[*] Lot of small changes

[-] srv files moved to lib-dap-chain-srv*
[*] Other moves and renames, sections->datums

[+] Declarations for chain operations
[+] Block cache
[+] Block dump
[*] Some internal fixes

[+] Wallet delcarations

[+] Transactions and transaction items
[*] Some renames mostly related to section