Ability to specify minor modes in `def-custom-package`
Load `rainbow-delimiters-mode` for `eval-expression-minibuffer-setup-hook`, `ielm-mode-hook`, and `lisp-interaction-mode-hook`
Add `rainbow-delimiters-mode` and `paredit-mode` to lisp major-modes via `def-custom-package`
Set colorised faces for `rainbow-delimiters-mode`
Customise `whitespace-mode`
Customize linum format