Don't show backtrace outside of development

Signed-off-by: Stephen Celis <stephen@stephencelis.com>
Add Crepe.logger

Signed-off-by: Stephen Celis <stephen@stephencelis.com>
Log exceptions in development

Signed-off-by: Stephen Celis <stephen@stephencelis.com>
Merge pull request #31 from stephencelis/logging

Basic logging support