Change name of snippets to override existing snippets

snippets/lisp-mode/defclass

@@ -1,8 +0,0 @@
-# -*- mode: snippet -*-
-# name: defclass
-# key: dc
-# --
-(defclass ${1:name} (${2:inherits})
-   (${4:slot})
-   (:documentation "${3:doc}"))
-$0

snippets/lisp-mode/defpackage

@@ -1,13 +0,0 @@
-# -*- mode: snippet -*-
-# contributor: Mark Karpov
-# name: my-defpackage
-# key: dp
-# --
-(defpackage     :${1:package}${2:
-  (:nicknames   ${3:nicks})}${4:
-  (:use         ${5:packages})}${6:
-  (:import-from ${7:packages})
-  (:shadow      ${8:packages})}${9:
-  (:export      ${10:packages})}${11:
-  (:documentation "${12:doc}")})
-$0

snippets/lisp-mode/my-defclass

@@ -0,0 +1,8 @@
+# -*- mode: snippet -*-
+# contributor: Mark Karpov
+# name: my-defclass
+# key: dc
+# --
+(defclass ${1:name} (${2:parents})
+  ($0)${3:
+  (:documentation "${4:doc}")})

snippets/lisp-mode/my-defpackage

@@ -0,0 +1,12 @@
+# -*- mode: snippet -*-
+# contributor: Mark Karpov
+# name: my-defpackage
+# key: dp
+# --
+(defpackage   :${1:package}${2:
+  (:nicknames ${3:nicks})}${4:
+  (:use       ${5:packages})}${6:
+  (:shadow    ${7:packages})}${8:
+  (:export    ${9:packages})}${10:
+  (:documentation "${11:doc}")})
+$0