Make RPC output same as Geth's for 2 RPC functions

[halfalicious]

Fix #5856

Make RPC output conform to Geth's output for debug_accountRange and eth_getTransactionCount.

[halfalicious]

Tested getTransactionCount but don't know how to call debug_accountRangeAt (function doesn't appear to be available in Geth's JS console) so would appreciate it if @gumb0 or @winsvega could give it a quick test.

[codecov-io]

Codecov Report

Merging #5866 into master will decrease coverage by 0.03%.
The diff coverage is 71.42%.

@@            Coverage Diff            @@
##           master   #5866      +/-   ##
=========================================
- Coverage   64.03%     64%   -0.04%     
=========================================
  Files         364     364              
  Lines       30970   30970              
  Branches     3434    3434              
=========================================
- Hits        19832   19822      -10     
- Misses       9913    9921       +8     
- Partials     1225    1227       +2

[gumb0]

To check debug_accountRange run scripts/dopple.py and use something like on Linux

curl http://127.0.0.1:8545 -X POST -d '{"jsonrpc":"2.0","method":"debug_accountRange","params":["1", 0, "0x0", 10],"id":68}'

or in Windows powershell

curl http://localhost:8545 -Method Post -Body '{"jsonrpc":"2.0","method":"debug_accountRange","params":["1", 0, "0x0", 10],"id":68}'

[halfalicious]

e.py and use s

To check debug_accountRange run scripts/dopple.py and use something like on Linux

curl http://127.0.0.1:8545 -X POST -d '{"jsonrpc":"2.0","method":"debug_accountRange","params":["1", 0, "0x0", 10],"id":68}'

or in Windows powershell

curl http://localhost:8545 -Method Post -Body '{"jsonrpc":"2.0","method":"debug_accountRange","params":["1", 0, "0x0", 10],"id":68}'

Ah thanks for the tip, i haven't been able to get dopple.py working on Windows but will give it a shot on Linux.

[gumb0]

Unit tests need fixing

[halfalicious]

Unit tests need fixing

Yup, there was a test which verified the string format. Fixed.

[halfalicious]

cc @gumb0