Fix sevopedia option to work from main menu

[karadoc]

Currently, the option to use the "sevopedia" instead of the civilopedia only works while playing. i.e. If it doesn't work if the civilopedia is accessed from the main menu before starting a game.

This is due to the fact that BUG only loads when the game start. (The BUG mod itself has the same problem, but they've chosen to use the sevopedia by default whereas K-Mod uses the normal civilopedia by default.)