Wrap flyspell-mode configuration in use-package
Add some org-mode tips
Do not let magit restore previous window config

Suppose the window configuration is side-by-side, and the magit-status
remains open on the right hand side. The buffer in the left hand side
window might be switched over time. It is odd to restore an old window
configuration after quitting magit.
Add package `org-mac-link`

Use C-c C-g to grab links in various applications on Mac OS.
Tweak org-reveal settings

* Remove `org-reveal-rolling-links' since org-reveal change the default
  value to nil in 7f4974d.
* Set `org-reveal-history' to t since it is useful to stay on the same
  slide in the browser after the file is updated.