Call package-initialize at the beginning of init.el to make sure
packages installed via the package manager are loaded and available to
code referencing them later on in the file.

By default, packages installed via the package manager are
loaded *after* init.el is evaluated. As a consequence, for referencing
code installed via the package manager it was necessary to add the
appropriate directories to load-path. Calling package-initialize fixes
this. YAY! :)
Don't show start-up screen.