Removed TODO: conditional expression(s) for testing wheter or not plugin X is enabled.

- The only configuration that'll give an error on startup/usage
  if not enabled is SingleCompile, and a test for it was added in
  5f1c40d.
- Added checks for every single plugin would be overly tiresome,
  hard to maintain and wouldn't give a big gain seeing as most of
  the configuration is just changing (global) variables.
- Won't split bundles into a seperate bundles-file for the same
  reason; it's hard to maintain, will add a lot of conditionals
  just to make it work fine and the gain is sparse. I'm still
  not too happy with the current solutions since it could come
  of as bothersome to use this configuration if you want to remove
  or add some of the core plugins. Suggestions are welcome.