initial commit (add lru_cache class, enable trt_engine_op to use it)

change deconstructor

Formatting

Add test for changing input shapes

Dynamic input shapes test passes. Static mode and cached_input_shapes not implemented yet

enable to run network in tests multiple times

Fix and improve input shape cache. Change cached_engine_batch_sizes -> cached_engine_input_shapes

Formatting

Implement SerializeShapesString for TensorShapes too

All tests passing

Revert cached_engine_input_shapes -> cached_engine_batches.

Rename cached_engine_batches -> cached_engine_batch_sizes

Improve hash and remove < operator

Forgot to rename hasher

Fix formatting

remove commented out code

remove lru_cache mutex

change deconstructor and declaration order

Formatting and use default deconstructor

Use default deconstructor

Use Resource manager for LRU cache

Implement feedback. Bug with destructor of resources when not using singleton

Move allocator to TRTEngineCacheResource to fix segfault.

Merge changes from e51fa304