ggml : sync with sam.cpp (add SAM Vit H & L model support and fix SAM's output) ...

ggml : sync with sam.cpp (add SAM Vit H & L model support and fix SAM's output)  (#476)

* Add support for Vit H and Vit L SAM model checkpoints

* Add "eps" argument to ggml_norm and fix all examples

* Fix bias addition for ConvTranspose2D layers in SAM example

* Fix build when GGML_ALLOCATOR_DEBUG is enabled

* Use op params for the stride in CONV_TRANSPOSE_2D

Needed in order for the operation to work with ggml-alloc as
the previous implementation used ggml_new_i32, which uses strach buffers

We should remove new_i32 and new_f32 I think. new_f32 is used in a lot
of places.