* tile and repeat operator added in rely

* fix pylint

* fix make warnings

* comments addressed

* fix lint error

* comment addressed

* Fix bug in mxnet converter for slick_like

* More tolerance for topi_conv2d_NCHWc

* add stack op frontend

* concate moved

* topi stack added

* stack added

* fix stack bugs and tested

* conv2d alterlayout udpated for relay

* fix pylint

* fix cmake warnings

* cmake warnings fixed

* [RELAY][OP] Proposal

* Fix

* Fix test

* Add batch_dot and cpu schedule

* Add relay support for batch_dot

* Rename batch_dot to batch_matmul

* nits

* Add missing file

* Put batch_matmul and dense x86 schedule in separate files

* Fix pylint

* Remove unused import

* Add cuda schedule for batch_matmul

* Add test case with larger batch size

* Add batch_matmul in api doc

* Fix quantize pass rounding error

* Fix pylint and minor change

* bug fix

* move layout.h & layout.cc from relay to tvm

* change ConvertLayout in relay to bijectiveLayout->Forward/backward

* add first test case

* add LayoutAxis

* add LayoutAxis struct and compiles

* simplify BijectiveLayout rule consturct

* polish func name for Layout, move impl to .cc, remove Layout::defined(), add defined() checker

* partially add layout py support

* add layout test cases

* add doc for tvm.layout & tvm.bijective_layout

* fix lint

* fix lint

* fix layout name generation bug

* fix layout typo

* address comments and add topi.layout_transform

* layout.h->data_layout.h, test_lang_layout.py->test_lang_data_layout.py

* Add arange op

* Update docs

* Fix bug

* add sanity check in relay and mxnet frontend mapping

* lint

* nits

* pylint

* don't allow empty output from arange

* Remove empty test for arange

* Fix bug and update doc

* nms data race solved

* tst_topi_vision reference results are gonna be updated in PR #2353

* proposal nms_ir updated

* [TOPI][CUDA] Add faster-rcnn proposal op

* Fix doc

* Add global barrier

* Use vthread in argsort

* Update sort and nms ir

* Fix lint

* Update sort ir in ssd nms

* Add GEMM autotvm template for x86

* Fix tophub link

* Disable RPC server logging file delete

* Update dense autotvm template

* Fix tests

* Fix lint

* tweak

* Register two templates with different tags

* [TOPI] Add roi align

* Refactor bilinear in image resize

* Rename to roi_align_nchw

* Fix

[TOPI] Fix reduce behavior to be consistent with numpy

* Add mean and product operators

* Fix typo

* Fix lint

* fix test

* Fix gpu schedule

* Update doc

* remove mean from topi

* Add nnvm test

* Fix cuda schedule

* Remove cuda schedule