feat(AEX-2): Use hex string for signMessage response

[nduchak]

Extend verifyMessage with ability to accept buffer or hex

[mradkov]

Looks good!

[codecov]

Codecov Report

Merging #911 into develop will increase coverage by 0.2%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           develop     #911     +/-   ##
==========================================
+ Coverage    92.74%   92.94%   +0.2%     
==========================================
  Files           57       57             
  Lines         2935     2936      +1     
==========================================
+ Hits          2722     2729      +7     
+ Misses         213      207      -6

Impacted Files	Coverage Δ
.../utils/aepp-wallet-communication/rpc/wallet-rpc.js	98.93% <ø> (ø)	⬆️
es/account/memory.js	100% <100%> (ø)	⬆️
es/account/index.js	100% <100%> (ø)	⬆️
es/channel/handlers.js	79.27% <0%> (-0.46%)	⬇️
es/channel/internal.js	96.09% <0%> (+0.78%)	⬆️
es/utils/json-big.js	84.13% <0%> (+2.88%)	⬆️

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