added CMAKE_OPTIONS_EXTRA

CPU: Kill warnings

* deserialize fix to return the right outermost function

* fix tests

* more switches to print out/visualize shapes

* revert to shared argon lib

* installs argon headers

* -DINSTALLED_HEADERS_PATH=${CMAKE_INSTALL_PREFIX}/include

* formatg

* remove debug info

* revert

* revert back to cpp-master

* Main chunk of style description

* Edit code guide for readability as raw rst. Update subheadings with clearer delineation

* Minor edits

* Typo

* Fix warnings in zero-sized tests; fix zero-sized tests return vector type for comparison ops

* Revert changes to cpu_emitter

* Enable CPU backprop tests

* Fix to dot codegen for cases where n_reduction_axes != 1

Dynamically create and destroy mkldnn engine objects to work around f…

CPU: Introduce reshape fallback before we switch to Eigen tensors

* Fix project README to be current, new doxyfile config test, cleanup static dir of theme

* make sure new README gets added

* fixes on doc cleanup branch

* Add feedback from github reviews

* Fix core README again

* test relu fusion for argon backend and enable permutation over max op

1. AvgPoolBackprop type checking
2. Padding for max-pool op and kernel
3. Max pool backprop kernel, and integrating everything with CPU backend/serializer
3a. Add optional backpointer from the max pool backprop op to the forward prop op

* modify existing autodiff unit tests to test fprop cache

* cleanup

* fix compile error introduced with bad merge

* remove invalid negative/negative backwards power test

(Squashing this commit but going to leave the full log here, unlike the way I usually do things)

* Incremental work on compatibility with system requirements

* Lower cmake version requirement so we can work with CentOS 7.4

* Disambiguate isnan call (CentOS's compiler doesn't like it)

* Make external_tbb conditional on NGRAPH_CPU_ENABLE

* Make MKLDNN inclusion conditional on NGRAPH_CPU_ENABLE

* Roll back desperation change to Ubuntu 14.04 binaries

* De-revert copyright date change (arrgh)

* Revert change of TBB's hard-coded compiler choice to gcc

* Cleanup of modified CMake stuff

* Add broken support for building LLVM from source

* Explain modification to json.hpp required compiler version

* Make TBB optional, and on by default. To disable, cmake -DNGRAPH_TBB_ENABLE=FALSE

* Add reasonable default for LLVM's CMAKE_ASM_COMPILER so users don't have to specify it

* Force TBB disabled if CMake is too old to build it (for CentOS)

* Build LLVM OpenMP as external project

* Tweak LLVM build options

* Minor comment edit in cmake scripts

* Workaround (fix?) for codegen crashes on CentOS

* Add some header paths for CentOS to resource_generator; temporary(?) tweak to ignore nonexistent paths

* Remove CMake compatibility figleaf since LLVM will require 3.1+ anyway

* Fix the TBB-enable flag to default to on

* Remove hard-coded choice of clang as tbb compiler

* ln -s -> ln -sf in command to create link for OpenMP source dir

* Make OpenMP build so it doesn't require symlink

* Allow use of prebuilt LLVM if requested at cmake time

* Some INSTALL instructions

* Allow NGRAPH_USE_PREBUILT_LLVM to be set in environment variable

* Tweak CI cmake options to use prebuilt LLVM

* Remove debug messages

* Rework defaulting behavior for LLVM_TARBALL_URL and LLVM_SHA1_HASH

* Remove warning message for unavailable header file directories

Merge branch 'jbobba/mkldnn-outlining' of https://github.com/NervanaSystems/private-ngraph-cpp into jbobba/mkldnn-outlining