add processing of validators while block persist;
add validator structure with decoding/encoding;
add validator get from store;
add EnrollmentTX and StateTX processing;
add pubkey decode bytes, unique and contains functions;
Goreport:
neo-go/pkg/core/contract_state_test.go
Line 21: warning: "Contracto" is a misspelling of "Contraction" (misspell)
Line 64: warning: "Contracto" is a misspelling of "Contraction" (misspell)
neo-go/pkg/core/interop_neo.go
Line 420: warning: "succeedes" is a misspelling of "succeeds" (misspell)
neo-go/pkg/network/discovery.go
Line 118: warning: "succeded" is a misspelling of "succeeded" (misspell)
Line 128: warning: "successfuly" is a misspelling of "successfully" (misspell)