* CF for Sign, and extend element type capabilities for unary arithop CF

* CF for Ceiling and Floor

* Update CPU CF builders

* Update CPU CF builders

* CF for Not

* Add tests for new CPU CF folders

* Add tests for recently added CPU CF functors

* Add tests for non-CPU ceiling/floor CF

* Unit tests

* Add test for CPU folder

* CF for Sign, and extend element type capabilities for unary arithop CF

* CF for Ceiling and Floor

* Update CPU CF builders

* Update CPU CF builders

* Add tests for new CPU CF folders

* Add tests for recently added CPU CF functors

* Add tests for non-CPU ceiling/floor CF

* Unit tests

* Add tests for new CPU CF folders

* Add tests for recently added CPU CF functors

* CF for And and Or

* CF support for comparison ops

* Fix predicate for binary elementwise; add unit tests for non-arithmetic binops

* Update CPU CF builders

* Make validation a pass and add it after every pass by default

* cleanup

* update per review comments

* Switch plaid to new API for disabling  pass validation

* address review comment

* [MLIR] Enable affine dialect loop fusion

Enable affine dialect loop fusion in nGraph pipeline. It also adds an
opt flag to enable/disable it when ngraph-opt is in place. Fusion seems
to work for simple cases. It wasn't able to fuse dot + add, though, at
least in my test case. One example that worked:

Input:
  %6 = alloc() : memref<2500x2500xf32>
  affine.for %i3 = 0 to 2500 {
    affine.for %i4 = 0 to 2500 {
      %7 = load %arg0[%i3, %i4] : memref<2500x2500xf32>
      %8 = load %0[%i3, %i4] : memref<2500x2500xf32>
      %9 = addf %8, %7 : f32
      store %9, %6[%i3, %i4] : memref<2500x2500xf32>
    }
  }
  %10 = alloc() : memref<2500x2500xf32>
  affine.for %i5 = 0 to 2500 {
    affine.for %i6 = 0 to 2500 {
      %11 = load %arg2[%i5, %i6] : memref<2500x2500xf32>
      %12 = load %0[%i5, %i6] : memref<2500x2500xf32>
      %13 = addf %12, %11 : f32
      store %13, %10[%i5, %i6] : memref<2500x2500xf32>
    }
  }
  %14 = alloc() : memref<2500x2500xf32>
  affine.for %i7 = 0 to 2500 {
    affine.for %i8 = 0 to 2500 {
      %15 = load %10[%i7, %i8] : memref<2500x2500xf32>
      %16 = load %6[%i7, %i8] : memref<2500x2500xf32>
      %17 = addf %16, %15 : f32
      store %17, %14[%i7, %i8] : memref<2500x2500xf32>
    }
  }

Output:
  %8 = alloc() : memref<2500x2500xf32>
  affine.for %i3 = 0 to 2500 {
    affine.for %i4 = 0 to 2500 {
      %9 = load %arg2[%i3, %i4] : memref<2500x2500xf32>
      %10 = load %2[%i3, %i4] : memref<2500x2500xf32>
      %11 = addf %10, %9 : f32
      %12 = affine.apply #map2(%i3, %i4, %i3, %i4)
      %13 = affine.apply #map3(%i3, %i4, %i3, %i4)
      store %11, %0[%12, %13] : memref<1x1xf32>
      %14 = load %arg0[%i3, %i4] : memref<2500x2500xf32>
      %15 = load %2[%i3, %i4] : memref<2500x2500xf32>
      %16 = addf %15, %14 : f32
      %17 = affine.apply #map2(%i3, %i4, %i3, %i4)
      %18 = affine.apply #map3(%i3, %i4, %i3, %i4)
      store %16, %1[%17, %18] : memref<1x1xf32>
      %19 = affine.apply #map2(%i3, %i4, %i3, %i4)
      %20 = affine.apply #map3(%i3, %i4, %i3, %i4)
      %21 = load %0[%19, %20] : memref<1x1xf32>
      %22 = affine.apply #map2(%i3, %i4, %i3, %i4)
      %23 = affine.apply #map3(%i3, %i4, %i3, %i4)
      %24 = load %1[%22, %23] : memref<1x1xf32>
      %25 = addf %24, %21 : f32
      store %25, %8[%i3, %i4] : memref<2500x2500xf32>
    }
  }

* Rename MLIR_LLVM_OPTIONS to NGRAPH_MLIR_OPTIONS

Something like this works now:
NGRAPH_MLIR_OPTIONS="--enable-affine-loop-fusion=false"

* Disable loop fusion by default and fix typo

[MLIR] Fix bad merge on 2 MLIR changes

[MLIR] Re-compile sub-graph once on first invocation

Changes to get allow NNP to pass tests

* CF for Sign, and extend element type capabilities for unary arithop CF

* Update CPU CF builders

* CF for Sum

* style

* CF for Concat

* Switch from Nodes to Inputs/Outputs

API is synchronous per thread and threads are coordinated so that
we know when we hit the last iteration everything is done.
Using join() to gate end of iterations was introducing too much
overhead to timing as verified via checking traces.

* Convert some ops to use Output<Node> inputs

* Remove duplicate validation

* Some GetOutputElement changes to help with Output<Node>

* Review comments

* Deallocate all temp tensors before return

* style-apply

* remove unique_ptr from allocator static allocation

* - for default allocator return address of the static object on stack instead of returning ptr to dynamically allocated object

* Revert "- for default allocator return address of the static object on stack instead of returning ptr to dynamically allocated object"

This reverts commit 126b269cb298e6eb8b99b1b9a90d5aa7cf8fb948.

* use raw pointer in set_host_memory_allocator

* fix build error

* Finish moving things into test/backend

* Update CODEOWNERS for moved file

* Tweak GPU manifest for renamed test

* [MLIR] Fix naming convention in MLIR files

Add naming convention note per file to state which files should use
nGraph naming convention and which MLIR naming convention and align
naming convention in those files with such a note.

* Remove m-prefix

[CMAKE] Change CODEGEN error on windows to be more grammatically correct