GitLab

* batch message_func, reduce_func and update_func

Conflicts:
	python/dgl/backend/pytorch.py

* test cases for batching

Conflicts:
	python/dgl/graph.py

* resolve conflicts

* setter/getter

Conflicts:
	python/dgl/graph.py

* test setter/getter

Conflicts:
	python/dgl/graph.py

* merge DGLGraph and DGLBGraph

Conflicts:
	python/dgl/graph.py

Conflicts:
	python/dgl/graph.py

* batchability test

Conflicts:
	python/dgl/graph.py

Conflicts:
	python/dgl/graph.py

* New interface (draft)

Conflicts:
	_reference/gat_mx.py
	_reference/molecular-gcn.py
	_reference/molecular-gcn_mx.py
	_reference/multi-gcn.py
	_reference/multi-gcn_mx.py
	_reference/mx.py
	python/dgl/graph.py

* Batch operations on graph

Conflicts:
	.gitignore
	python/dgl/backend/__init__.py
	python/dgl/backend/numpy.py
	python/dgl/graph.py

* sendto

* storage

* NodeDict

* DGLFrame/DGLArray

* scaffold code for graph.py

* clean up files; initial frame code

* basic frame tests using pytorch

* frame autograd test passed

* fix non-batched tests

* initial code for cached graph; tested

* batch sendto

* batch recv

* update routines

* update all

* anonymous repr batching

* specialize test

* igraph dep

* fix

* fix

* fix

* fix

* fix

* clean some files

* batch setter and getter

* fix utests