ARROW-6175: [Java] Fix MapVector#getMinorType and extend AbstractContainerVector addOrGet complex vector API

[tianchen92]

Related to ARROW-6175.

i. Currently MapVector#getMinorType extends ListVector which returns the wrong MinorType.
ii. AbstractContainerVector now only has addOrGetList, addOrGetUnion, addOrGetStruct which not support all complex type like MapVector and FixedSizeListVector.

[codecov-io]

Codecov Report

Merging #5043 into master will increase coverage by 2.1%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #5043      +/-   ##
==========================================
+ Coverage   87.57%   89.68%    +2.1%     
==========================================
  Files        1008      670     -338     
  Lines      143790    99342   -44448     
  Branches     1418        0    -1418     
==========================================
- Hits       125926    89091   -36835     
+ Misses      17502    10251    -7251     
+ Partials      362        0     -362

Impacted Files	Coverage Δ
cpp/src/plasma/thirdparty/ae/ae.c	70.75% <0%> (-0.95%)	⬇️
cpp/src/arrow/util/thread-pool-test.cc	97.66% <0%> (-0.94%)	⬇️
r/src/recordbatch.cpp
r/R/Table.R
js/src/util/fn.ts
go/arrow/array/bufferbuilder.go
r/src/symbols.cpp
rust/datafusion/src/execution/projection.rs
rust/datafusion/src/execution/filter.rs
rust/arrow/src/csv/writer.rs
... and 331 more

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[emkornfield]

+1, LGTM.