Add nested IValue list and tuple support

[frankfliu]

Change-Id: I41761821f2a605b2c69be95cff109b0761ba4990

Description

Brief description of what this PR is about

• If this change is a backward incompatible change, why must this change be made?
• Interesting edge cases to note here

[codecov-commenter]

Codecov Report

Merging #1208 (54cc1ff) into master (df1a805) will increase coverage by 0.09%.
The diff coverage is 100.00%.

@@             Coverage Diff              @@
##             master    #1208      +/-   ##
============================================
+ Coverage     70.51%   70.60%   +0.09%     
- Complexity     5006     5016      +10     
============================================
  Files           476      476              
  Lines         21960    21964       +4     
  Branches       2320     2320              
============================================
+ Hits          15484    15508      +24     
+ Misses         5276     5255      -21     
- Partials       1200     1201       +1     

Impacted Files	Coverage Δ
...c/main/java/ai/djl/pytorch/jni/PyTorchLibrary.java	100.00% <ø> (ø)
...ngine/src/main/java/ai/djl/pytorch/jni/IValue.java	95.09% <100.00%> (+19.58%)	⬆️
api/src/main/java/ai/djl/repository/Artifact.java	87.80% <0.00%> (-1.63%)	⬇️
api/src/main/java/ai/djl/inference/Predictor.java	90.38% <0.00%> (+2.88%)	⬆️

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[stu1130]

nit: torch::IValue