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

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 !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 !979 from ms_yan/rename_columns

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 !477 from xiefangqi/xfq_fix_voc

Initial commit for dataset op python

Added signature to barrier

Adde compiling barrier code

Rebasing, fixed new compile errors

Final fix for make_unique

Added pybind API for barrier

Fixed pyfunc invocation

python interface - sync_wait

!1 sync_wait python interface
* python interface - sync_wait

fix test

update test

update test

Added new test case

add test case

test for shuffle + batch

Added two-sync test case

Restrited that no shuffle after sync

Added sync to pipeline info

block first databuffer as well

Intelligently get batch size

Fix default case

Lock Pair shares among all iterators

Added fix for empty character

Fixed up test case formatting

Fix end of epoch in sync_wait

Fixing CI

Merge pull request !460 from xulei/filter_master

Merge pull request !404 from JunhanHu/python_sampler_for_cpp_dataset

Merge pull request !194 from pengyanjun/fix_dataset_para_validator_check

Signed-off-by: leonwanghui <leon.wanghui@huawei.com>