documented :cd and :pwd commands

doc/cli/cli.txt

@@ -13,11 +13,13 @@ The CLI shows a prompt where commands can be entered, which are then executed by
 
 ! Command	Short version	Description
 | @:help@	@:?@		Show a help screen describing the available commands.
-| @:quit@	@:q@		Quit the interactive cli.
+| @:quit@	@:q@		Exit the MSE command line interface.
 | @:load@	@:l@		Load a set file. The current set will be unloaded.
 		 		For example:
 		 		]:load my-set.mse-set
 | @:reset@	@:r@		Clear all variable definitions.
+| @:cd@		@:c@		Change the working directory.
+| @:pwd@	@:p@		Print the current working directory.
 | @:!@		 		Perform a shell command. For example @:! dir@ shows a directory listing.
 | ''other''	 		Execute the command as a line of [[type:script]] code.
 		 		The script has access to the loaded set and all [[fun:index|built in functions]].

src/cli/cli_main.cpp

@@ -102,7 +102,7 @@ void CLISetInterface::showUsage() {
 	cli << _("   :quit               Exit the MSE command line interface.\n");
 	cli << _("   :reset              Clear all local variable definitions.\n");
 	cli << _("   :pwd                Print the current working directory.\n");
-	cli << _("   :cd                 Change working directory.\n");
+	cli << _("   :cd                 Change the working directory.\n");
 	cli << _("   :! <command>        Perform a shell command.\n");
 	cli << _("\n Commands can be abreviated to their first letter if there is no ambiguity.\n\n");
 }