Feature/extcodehash

[llwslc]

What does this PR do?
To provide a new opcode, which returns the keccak256 hash of a contract's code.

Why are these changes required?
Many contracts need to perform checks on a contract's bytecode, but do not necessarily need the bytecode itself.

This PR has been tested by:

• Unit Tests
• Manual Testing

Follow up

Extra details
tronprotocol/TIPs#30

[codecov-io]

Codecov Report

Merging #2075 into develop will increase coverage by 1.45%.
The diff coverage is 62.2%.

@@              Coverage Diff              @@
##             develop    #2075      +/-   ##
=============================================
+ Coverage      43.46%   44.92%   +1.45%     
- Complexity      4036     4219     +183     
=============================================
  Files            510      503       -7     
  Lines          29596    29935     +339     
  Branches        3054     3119      +65     
=============================================
+ Hits           12863    13447     +584     
+ Misses         15569    15263     -306     
- Partials        1164     1225      +61

Impacted Files	Coverage Δ	Complexity Δ
...org/tron/core/actuator/ProposalCreateActuator.java	42.3% <0%> (-1.35%)	23 <0> (ø)
src/main/java/org/tron/core/db/Manager.java	43.02% <0%> (-0.25%)	120 <0> (+3)
...java/org/tron/core/witness/ProposalController.java	49.53% <0%> (-0.95%)	14 <0> (ø)
...g/tron/common/runtime/vm/PrecompiledContracts.java	7.11% <0%> (-0.07%)	2 <0> (ø)
...main/java/org/tron/common/runtime/RuntimeImpl.java	63.52% <100%> (+0.27%)	56 <0> (+2)	⬆️
...c/main/java/org/tron/common/runtime/vm/OpCode.java	98.48% <100%> (+0.54%)	17 <0> (ø)	⬇️
...in/java/org/tron/common/runtime/vm/EnergyCost.java	72.97% <100%> (+0.49%)	27 <1> (+1)	⬆️
src/main/java/org/tron/core/config/Parameter.java	100% <100%> (ø)	0 <0> (ø)	⬇️
src/main/java/org/tron/core/Wallet.java	14.77% <15.38%> (+0.57%)	45 <1> (+3)	⬆️
.../java/org/tron/common/runtime/config/VMConfig.java	71.42% <57.14%> (-2.49%)	13 <5> (+2)
... and 190 more

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[BlueHoopor]

refer to #2238 (comment)