Add Portable Mode

[SmilerRyan]

Since this is useful for testing purposes i would like to have a "portable" mode, where all profiles etc are forced to be stored in the same folder as the executable if a portable.txt file exists.

[SmilerRyan]

Adding onto this from observations I have made to get closer to this, manually setting THESEUS_CONFIG_DIR to UserData then launching it with command prompt gets you most of the way there, however these files still get left behind:

C:\Users\User\AppData\Local\AstralRinthApp\EBWebView C:\Users\User\AppData\Roaming\AstralRinthApp\app-window-state.json

Although not optimal, another approach if possible is to somehow set userprofile to . and then create appdata\local and appdata\roaming folders on start.