Allow to set a SetLibrarySearchPath in the golang bindings (#981)

This is used to identify the path where all the various implementations
are

gpt4all-bindings/golang/README.md

@@ -45,7 +45,7 @@ To use the bindings in your own software:
 
 - Import `github.com/nomic-ai/gpt4all/gpt4all-bindings/golang`;
 - Compile `libgpt4all.a` (you can use `make libgpt4all.a` in the bindings/go directory);
-- Link your go binary against whisper by setting the environment variables `C_INCLUDE_PATH` and `LIBRARY_PATH` to point to the `binding.h` file directory and `libgpt4all.a` file directory respectively.
+- Link your go binary by setting the environment variables `C_INCLUDE_PATH` and `LIBRARY_PATH` to point to the `binding.h` file directory and `libgpt4all.a` file directory respectively.
 - Note: you need to have *.so/*.dynlib/*.dll files of the implementation nearby the binary produced by the binding in order to make this to work
 
 ## Testing

gpt4all-bindings/golang/gpt4all.go

@@ -10,6 +10,7 @@ package gpt4all
 //                            float top_p, float temp, int n_batch,float ctx_erase);
 // void free_model(void *state_ptr);
 // extern unsigned char getTokenCallback(void *, char *);
+// void llmodel_set_implementation_search_path(const char *path);
 import "C"
 import (
 	"fmt"
@@ -27,6 +28,10 @@ type Model struct {
 func New(model string, opts ...ModelOption) (*Model, error) {
 	ops := NewModelOptions(opts...)
 
+	if ops.LibrarySearchPath != "" {
+		C.llmodel_set_implementation_search_path(C.CString(ops.LibrarySearchPath))
+	}
+
 	state := C.load_model(C.CString(model), C.int(ops.Threads))
 
 	if state == nil {

gpt4all-bindings/golang/options.go

@@ -24,7 +24,8 @@ var DefaultModelOptions ModelOptions = ModelOptions{
 }
 
 type ModelOptions struct {
-	Threads int
+	Threads           int
+	LibrarySearchPath string
 }
 type ModelOption func(p *ModelOptions)
 
@@ -100,6 +101,13 @@ func SetThreads(c int) ModelOption {
 	}
 }
 
+// SetLibrarySearchPath sets the dynamic libraries used by gpt4all for the various ggml implementations.
+func SetLibrarySearchPath(t string) ModelOption {
+	return func(p *ModelOptions) {
+		p.LibrarySearchPath = t
+	}
+}
+
 // Create a new PredictOptions object with the given options.
 func NewModelOptions(opts ...ModelOption) ModelOptions {
 	p := DefaultModelOptions