Implement delegated voting

[fyrchik]

Close #867 .
Close #1206 .

Tested voting CLI on single node via getvalidators RPC.

[codecov]

Codecov Report

Merging #1252 into master will increase coverage by 6.81%.
The diff coverage is 47.18%.

@@            Coverage Diff             @@
##           master    #1252      +/-   ##
==========================================
+ Coverage   61.26%   68.07%   +6.81%     
==========================================
  Files         216      217       +1     
  Lines       18490    18558      +68     
==========================================
+ Hits        11328    12634    +1306     
+ Misses       6542     5235    -1307     
- Partials      620      689      +69     

Impacted Files	Coverage Δ
cli/wallet/wallet.go	0.00% <0.00%> (ø)
pkg/core/native/native_gas.go	69.69% <0.00%> (ø)
pkg/core/native/validators_count.go	0.00% <ø> (ø)
pkg/rpc/client/nep5.go	3.60% <0.00%> (+3.60%)	⬆️
pkg/core/state/native_state.go	72.60% <46.66%> (-7.73%)	⬇️
pkg/core/util.go	76.76% <60.00%> (-2.59%)	⬇️
pkg/core/native/native_neo.go	55.51% <61.00%> (+20.95%)	⬆️
pkg/core/blockchain.go	66.70% <66.66%> (+1.79%)	⬆️
pkg/core/native/native_neo_candidate.go	82.60% <82.60%> (ø)
pkg/core/native/native_nep5.go	72.88% <88.88%> (+1.69%)	⬆️
... and 35 more

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[roman-khimov]

I think we need to differentiate GetStandbyValidators from GetStandbyCommittee in Blockchain API. We'll have more members in standby committee soon.

outdated