Address code warnings

Signed-off-by: Steffan Westcott <steffan.westcott@clicktravel.com>
Merge branch 'master' of github.com:ClickTravel/Cheddar
IAM-138 Enable custom behaviour when failing to map element in collection

Signed-off-by: Steffan Westcott <steffan.westcott@clicktravel.com>
Merge pull request #40 from clicktravel-steffan/master

IAM-138 Enable custom behaviour when failing to map element in collection