hd: add alias page (#10873)

Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>

pages/common/hd.md

@@ -0,0 +1,8 @@
+# hd
+
+> This command is an alias of `hexdump`.
+> More information: <https://manned.org/hd.1>.
+
+- View documentation for the original command:
+
+`tldr hexdump`