#22 Backend: Update a Team
Merge branch '22-backend-update-a-team'
#23 Backend: Delete a Team

Merge branch 'master' of https://github.com/xliquidzz/jasmin into 23-backend-delete-a-team

Conflicts:
	src/main/java/ch/fihlon/jasmin/dao/TeamDAO.java
	src/main/java/ch/fihlon/jasmin/resources/TeamResource.java
Merged Pull Request #24 for Issue #23 Backend: Delete a Team
#15 Backend: Create a Product Backlog Item
Merge branch '15-backend-create-a-product-backlog-item'
#16 Backend: Read a Product Backlog Item
Merge branch '16-backend-read-a-product-backlog-item'
#17 Backend: Update a Product Backlog Item
Merge branch '17-backend-update-a-product-backlog-item'
#18 Backend: Delete a Product Backlog Item
Merge branch '18-backend-delete-a-product-backlog-item'
#26 Add Nonnull and Nullable to all classes
Merge branch '26-add-nonnull-and-nullable-to-all-classes'
#28 Backend: A Team should not be deleteable if it has Product Backlog Items assigned
Merge branch '28-backend-a-team-should-not-be-deleteable-if-it-has-product-backlog-items-assigned'
#30 Rename Item to Product Backlog Item
Merge branch '30-rename-item-to-backlog-item'
#25 Backend: Read all Sprint Backlog Items of a particular Sprint
Merge branch '25-backend-read-all-sprint-backlog-items-of-a-particular-sprint'