[TOPI] Specify non-zero absolute tolerance in tests (#1925)

apps/extension/tests/test_ext.py

docs/deploy/aocl_fpga.md

docs/deploy/aws_fpga.md

nnvm/python/nnvm/testing/check_computation.py

nnvm/tests/python/compiler/test_build.py

nnvm/tests/python/compiler/test_compiler_cache.py

nnvm/tests/python/compiler/test_fold_axis.py

nnvm/tests/python/compiler/test_nhwc_layout.py

nnvm/tests/python/compiler/test_op_fusion.py

nnvm/tests/python/compiler/test_optimizer.py

nnvm/tests/python/compiler/test_param_dict.py

nnvm/tests/python/compiler/test_rpc_exec.py

nnvm/tests/python/compiler/test_top_assign.py

nnvm/tests/python/compiler/test_top_level2.py

nnvm/tests/python/compiler/test_top_level4.py

nnvm/tests/python/frontend/coreml/test_forward.py

nnvm/tests/python/frontend/darknet/test_forward.py

nnvm/tests/python/frontend/keras/test_forward.py

nnvm/tests/python/frontend/mxnet/test_forward.py

nnvm/tests/python/frontend/onnx/test_forward.py