Removed extra fields in schema

Fixed test cases

Fixing CI

init remove storage op test case c++

remove source c++ files

remove graphengine changes

concat op

Truncate Pair

concat_op

remove graph engine changes

-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

change to use __add__ operation instead ds.concat

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