* Handle models in prototxt format.
Signed-off-by: Adam Rogowiec <adam.rogowiec@intel.com>

* Convert Onnx models to text format.

* Tool for conversion between protobuf ONNX models in binary and text format.
Signed-off-by: Adam Rogowiec <adam.rogowiec@intel.com>

* Update ONNX test models text format.

* Convert ONNX LSTM model to text format.

* Rename and make second argument optional.

* Unify models metadata.

* Remove onnx binary models.

* Review: fix comments.

* Fix not yet updated models extension in UTs.

* Add UT with binary protobuf models.

* Clang format.

* Remove failing UT in prototxt since it has problems with CI.

* Inhibit logging protobuf errors.

* Revert "Remove failing UT in prototxt since it has problems with CI."

This reverts commit 94741a8c4594f3cc2ebdca428fa40b94a79240c2.

* Remove LogSilencer from onnx importer api and remove respective UT.

* Conversion script updates