Move content in the buildtools repo into paddle repo

[wangkuiyi]

Fixes https://github.com/PaddlePaddle/buildtools/issues/11

[wangkuiyi]

@typhoonzero Do we really need the root subdirectory? According to

https://github.com/PaddlePaddle/buildtools/blob/6839c22073076f3f5ad7a9f8b9e54c51ba4e82f6/manylinux/Dockerfile-x86_64#L42

it seems that this directory is to add a development environment into the releasing Docker image. But we are not supposed to use these images for development, right?

[wangkuiyi]

I didn't change any source code, but a unit test failed during CI:

[13:07:38]	276/316 Test #276: test_detection_output_op ....................***Failed 1.63 sec
[13:07:38]	F
[13:07:38]	======================================================================
[13:07:38]	FAIL: test_check_output (__main__.TestUnpoolOp)
[13:07:38]	----------------------------------------------------------------------
[13:07:38]	Traceback (most recent call last):
[13:07:38]	File "test_detection_output_op.py", line 45, in test_check_output
[13:07:38]	self.check_output()
[13:07:38]	File "/paddle/python/paddle/v2/fluid/tests/op_test.py", line 321, in check_output
[13:07:38]	self.check_output_with_place(place, atol)
[13:07:38]	File "/paddle/python/paddle/v2/fluid/tests/op_test.py", line 310, in check_output_with_place
[13:07:38]	"Output (" + out_name + ") has diff at " + str(place))
[13:07:38]	AssertionError: Output (Out) has diff at CUDAPlace(0)
[13:07:38]	
[13:07:38]	----------------------------------------------------------------------
[13:07:38]	Ran 1 test in 0.006s
[13:07:38]	
[13:07:38]	FAILED (failures=1)

[typhoonzero]

@wangkuiyi

it seems that this directory is to add a development environment into the releasing Docker image. But we are not supposed to use these images for development, right?

Yes, root directory is not needed any more, we should use Dockerfile under Paddle repo as development environment.

[typhoonzero]

Seems style check has error, original python code under buildtools repo didn't use pre-commit to check the style.

[typhoonzero]

LGTM!