Fix help for replacements

Author: Your Name

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "frida-cshell",
-  "version": "1.6.6",
+  "version": "1.6.7",
   "description": "Frida's CShell",
   "scripts": {
     "prepare": "npm run build && npm run version && npm run package && npm run copy",

package.json

@@ -27,9 +27,14 @@ export class ReplaceCmdLet extends CmdLetBase {
 
   private static readonly USAGE: string = `Usage: replace
 
+replace - show all replacements
+
 replace dest src - replace function
-  dest   the address/symbol to replace
-  src    the address/symbol to replace with`;
+  dest   the address/symbol of the function to replace
+  src    the address/symbol of the function to replace with
+
+replace ${CmdLetBase.NUM_CHAR}n ${CmdLetBase.DELETE_CHAR} - delete a replacement
+  ${CmdLetBase.NUM_CHAR}n     the number of the replacement to delete`;
 
   public runSync(tokens: Token[]): Var {
     const retDelete = this.runDelete(tokens);