Adding support for multidimensional arrays arguments in the contract wrapper generator

[fergarrui]

This should fix #110 and fix #271 .
It also supports nested dynamic arrays. It won't compile in Solidity, but since that feature should be added in the future, it does not hurt to have it already here. For example:

uint256[][]

[codecov]

Codecov Report

Merging #404 into master will increase coverage by 0.09%.
The diff coverage is 88.57%.

@@             Coverage Diff              @@
##             master     #404      +/-   ##
============================================
+ Coverage     76.55%   76.64%   +0.09%     
- Complexity     1627     1632       +5     
============================================
  Files           215      215              
  Lines          6064     6092      +28     
  Branches        955      960       +5     
============================================
+ Hits           4642     4669      +27     
+ Misses         1193     1192       -1     
- Partials        229      231       +2

Impacted Files	Coverage Δ	Complexity Δ
abi/src/main/java/org/web3j/abi/Utils.java	81.96% <80%> (-0.39%)	19 <2> (+2)
...ava/org/web3j/codegen/SolidityFunctionWrapper.java	95.75% <92%> (-0.25%)	107 <1> (+3)
...ore/src/main/java/org/web3j/utils/Observables.java	80% <0%> (-4%)	9% <0%> (-1%)
...main/java/org/web3j/abi/datatypes/StaticArray.java	100% <0%> (+18.18%)	10% <0%> (+1%)	⬆️

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[conor10]

Thanks @fergarrui - looks good so far. There's an additional piece of further testing that I'd like to have added.

The following tests generate smart contract wrappers and verify that the generated code compiles. Please can you update the existing Arrays.sol smart contract to use multi-dimensional arrays in addition to single as it currently does?

[conor10]

Great work!