Add Path functions (#505)

* Add Path functions

* Add unit tests

pkg/stdlib/path/separate.go

@@ -0,0 +1,33 @@
+package path
+
+import (
+	"context"
+	"path"
+
+	"github.com/MontFerret/ferret/pkg/runtime/core"
+	"github.com/MontFerret/ferret/pkg/runtime/values"
+	"github.com/MontFerret/ferret/pkg/runtime/values/types"
+)
+
+// Separate separates the path into a directory and filename component.
+// @param path (String) - The path
+// @returns (Array) - First item is a directory component, and second is a filename component.
+func Separate(_ context.Context, args ...core.Value) (core.Value, error) {
+	err := core.ValidateArgs(args, 1, 1)
+
+	if err != nil {
+		return values.None, err
+	}
+
+	err = core.ValidateType(args[0], types.String)
+
+	if err != nil {
+		return values.None, err
+	}
+
+	pattern, name := path.Split(args[0].String())
+
+	arr := values.NewArrayWith(values.NewString(pattern), values.NewString(name))
+
+	return arr, nil
+}