Default use-package-verbose to nil
Backward compatibility with emacs-22.1

This change supports the emacs that ships with MacOS X, the last version not encumbered by GPLv3.
Merge pull request #67 from dabrahams/patch-1

Backward compatibility with emacs-22.1
fboundp is a function, not a variable

Fixes #68
Add a :demand directive, to override deferred loading (#65)