Load languages directly from the directory

[vE5li]

Currently there is a hardcoded Language enum in localization/mod.rs that defines all supported languages. This enum can be removed and the client could instead load the supported languages from the language directory (archive/data/languages) directly.

The main benefit is that adding a new language does not require modifying or recompiling Korangar.

For this issue to be complete the PR needs to:

• Add a field to the Localization that defines the display name of the language (currently this is hard-coded)
• Update the Interface Settings window drop down options
• Update the language files test in localization/mod.rs
• Remove the Language enum