As a pet store manager, I need a web system to manage pets information.
AC1: I can add new pet to the system. The information I need to input include:
name(unique)
type(dog or cat)
color
price
AC2: I can see the information of all pets in the system.
AC3: I can find pet by its name.
AC4: When a pet was bought by customer, I can get it off the shelf.
AC5: I can modify the price of a pet.
AC6: I can find pets by type.
AC7: I can find pets by price range.
AC8: I can find pets by color.