* speed up reduceslice with kernel emitter

* const-ify and fix a clang warning

* add elementwise ops, slice to for loops

* add broadcast codegen

* add Exp

* fix bugs introduced in eigen kernels

* fix another introduced bug in Eigen

* Fix an Atomic Bug with Sum, do some cleanup

* unit tests pass

* Add Reshape Op, passes Tests

* rewrite sum to correctly handle muti-threading

* Code Cleanup

* add some extra unary ops

* Address review comments

* fix an error in the review comment refactor

* Add Power op

* Add (most) of the Logic Ops

* Make Concat default to OpenMP kernel

* fix n-D reshape issue