* update nbench output to be more consistent for single vs. directory benchmark.

* wip

* add types used in model

* fix test

* style

* catch all exceptions when running any option

* add unsupported_op exception

* unsupported_op test

* add printout of unsupported op in model

* fix GPU dispatcher check

* fix test designation

* catch exceptions on single file runs too

* add unsupported_op exception where needed

* remove unsupported_op class

* add unassigned op exception

* add unit test

* catch unsupported op in nbench

* add cpu test back

* update all latest merges

* mode change

* add option to copy intput/output data for each iteration

* add support for stale buffers

* only print details if details enabled

* refactor print routines to main file

* refactor for multi dir support

* dir support prints nice results

* use line comments instead of multiline comments for license header

* update more

* update new files

* more header updates

* style

* Add an option to exclude the first iteration

* Switch to warmup iterations

* Cleanup

* add option to run all models in a directory

* add print for exception from benchmark

* nbench cleanup

* update style

* Move runtime::Manager functionality into runtime::Backend

* Remove unused files

* remove obsolete function

* remove deprecated

* remove all legacy Backend API usage

remove deprecated files

* pull in changes from master

* fix GPU calls

* disable tests in convolution generator

* update per PR comments. Enable performance counter feature.

* update per PR comments

* fix build error

* fix conditionally compiled test :(

* add visualize option to nbench

* check for dot, amend help msg

* fix detailed timing flag

* more detailed info