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ARROW-4225: [Format][C++] Add CSC sparse matrix support

I'd like to add CSC sparse matrix support in format and C++ API.

This pull-request changes both format and C++ API.

The changes in format are below:

- The new field `compressedAxis` is added to `SparseMatrixIndexCSR` table; this field used to distinguish CSR and CSC
- `SparseMatrixIndexCSR` is renamed to `SparseMatrixIndexCSX`

The changes in C++ API are below:

- `SparseCSCIndex` class is added as a subclass of `internal::SparseCSXIndex`
- `internal::SparseCSXIndex` class is added as a superclass of `SparseCSRIndex` and `SparseCSCIndex` classes
- `SparseCSCMatrix` class is added as an alias to `SparseTensorImpl<SparseCSCIndex>` class
- `ReadSparseTensor` supports reading `SparseCSCMatrix` class

Closes #5932 from mrkn/ARROW-4225 and squashes the following commits:

013f6381e <Kenta Murata> Use enum class for SparseMatrixCompressedAxis
28307dbdf <Kenta Murata> Add shape validation in ReadSparseCSXIndex
7f1d7f8e3 <Kenta Murata> Fix comments
25edf4620 <Kenta Murata> Combine CheckSparseTensorRoundTrip for CSR and CSC
42df6b5ca <Kenta Murata> Rename TYPE_NAME to kTYPE_NAME
269640f59 <Kenta Murata> Define format_id in subclasses
25177c5d4 <Kenta Murata> Use TypeError
1c3c541e0 <Kenta Murata> Update comment
878a08ff8 <Kenta Murata> Anonymize some functions
89a7ddce7 <Kenta Murata> Remove needless return
635f8ffdc <Kenta Murata> Add IPC support
4ce999f88 <Kenta Murata> Add SparseCSCIndex and SparseCSCMatrix
60e6b2a1f <Kenta Murata> Introduce internal::SparseCSXIndex
6f85b4cef <Kenta Murata> Update flatbuffers generated files
308a0f35e <Kenta Murata> Replace SparseMatrixIndesCSR with SparseMatrixIndexCSX

Authored-by: Kenta Murata <mrkn@mrkn.jp>
Signed-off-by: Antoine Pitrou <antoine@python.org>