Resource manager for texts about openmu

[sven-n]

Thanks for your input. Localization of these messages was already on my radar, but wasn't important enough yet.

It should not be a big issue to solve this. A solution could look like this:
First, we need the culture settings a specific client prefers. We could add a property in the Account or maybe the game client already sends us this information. The original game launcher of GMO Season 6E3 has a setting for the language. I expect that this setting is sent to the server in the login process.

Then we need to copy or move all message strings which are sent to the client to the resources and replace this occurrences by calling the ResourceManager.