GitLab

* Several optimizations on DGL-KG:
1. Sorted positive edges for sampling which can reduce random
   memory access during positive sampling
2. Asynchronous node embedding update
3. Balanced Relation Partition that gives balanced number of
   edges in each partition. When there is no cross partition
   relation, relation embedding can be pin into GPU memory
4. tunable neg_sample_size instead of fixed neg_sample_size

* Fix test

* Fix test and eval.py

* Now TransR is OK

* Fix single GPU with mix_cpu_gpu

* Add app tests

* Fix test script

* fix mxnet

* Fix sample

* Add docstrings

* Fix

* Default value for num_workers

* Add soft relation part

* Upd

* Some fix

* upd

* Now work

* Fix TransR

* Fix eval and add some doc string

* triger

* upd

* Add some training scripts for freebase multi-gpu

* upd

* upd

* upd