user shall be able to create a goal to track taking enough nutrients

[muatik]

user shall be able to create a goal to track whether he or she is taking enough nutrients in a given time period.

To activate this goal, user should provide the following form data:

• time period (daily or weekly)
• for each nutrient to be tracked
  • nutrient's name (e.g. Vitamin A, iron...)
  • an appropriate unit (e.g. mg/g)
  • amount

User can add as many nutrients as he or she desires; however, there must be at least one nutrient to activate the goal.

As long as the goal is activated, period or nutrients list cannot be changed. To change them, the goal should be deactivated first.

6.1.1. https://docs.google.com/document/d/1JM05Z4752BKu_EsHfXURPDfS_2sqV1slaiLKKQlkuWk/