Add osay command (#13057)

* add osay command

* replace obsolete method

* inherit LocalizedCommands instead of IConsoleCommand

* streamline

* make OSay class public to match other commands

* re-scope namespace to file

Resources/Locale/en-US/administration/commands/osay-command.ftl

@@ -0,0 +1,9 @@
+osay-command-description = Forces another entity to try to send a message
+osay-command-help-text = Usage: {$command} <uid> <type> <message>
+
+osay-command-arg-uid = source uid
+osay-command-arg-type = type
+osay-command-arg-message = message
+
+osay-command-error-args = Invalid number of arguments
+osay-command-error-euid = {$arg} is not a valid entity uid.