hdiutil: add page (#3389)

pages/osx/hdiutil.md

@@ -0,0 +1,19 @@
+# hdiutil
+
+> Utility to create and manage disk images.
+
+- Mount an image:
+
+`hdiutil attach {{filename}}`
+
+- Unmount an image:
+
+`hdiutil detach /Volumes/{{volumename}}`
+
+- List mounted images:
+
+`hdiutil info`
+
+- Create an ISO image from the contents of a directory:
+
+`hdiutil makehybrid -o {{filename}} {{dirname}}`