Merge pull request !1509 from ms_yan/r0.3_split

Cleanup dataset UT: restore config support

Merge pull request !1470 from heleiwang/r0.3_fix_log

Merge pull request !1308 from h.farahat/string_tensor2

add support for MindRecord and TFRecord
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optimize tensorshape

optimize tensorshape and FlatIndex

TFRecord and MindRecord support for string tensor

Modify mem layout
Add new constructor
Add method Allocate

Change some GetMutableBuffer usages to AllocateBuffer

Merge pull request !1281 from Peilin/splitOp

implementation 99% complete

everything and tested except for repeatable shuffling

tested most basic/typical split usecases

cleanup

some more cleanup

fix CI

more ci fix

more ci fixes

more ci fix

more ci fix

more ci fix

added more tests, fixed some bugs

some more clean up and test cases

added shard/shuffle before split warning/error

addressed code review comments and ci

fixed ci

Merge pull request !1318 from xiefangqi/xfq_fix_batch_log

Merge pull request !1235 from xiefangqi/xfq_del_CRLF

-replace switch'case by indexing

- Add test case
- Add constructors
- Add getItem string

- Fix bugs
- Add more tests

- Tensor iterator
- asNumpy
- TextFileDataset

- Tensor(Numpy)

- Super > 2D
- Add more test cases for GeneratorDataset

- Change StartAddr to GetBuffer and GetMutableNuffer

- Raise an error if batch is used with strings

Clean-up work

Merge pull request !1157 from ms_yan/concat_dataset

Merge pull request !1126 from xiefangqi/voc_support_detection

change to use __add__ operation instead ds.concat

Merge pull request !924 from chenweifeng/dataset

clang format updates

self-review cleanups

cpplint fix

review updates

ci fixes

Merge pull request !978 from xulei/filter_op

Merge pull request !979 from ms_yan/rename_columns

Merge pull request !507 from ZiruiWu/batch_with_padding

support for 1 specific dimension to be None, added validator

fix various CI complains

another round of CI fixes

ci

refactor parts of the code

code refactor

ci fix

comments added, fix bugs

address review comments

address review comments

review cmts

added simple perf test script

update pad code

perf imprv

Merge pull request !869 from JesseKLee/random_data_op