Make design decisions for labels

[csansone]

Labels in Trello are a bit complicated, in that they are assigned at the board level and at the card level.

For example, a simple command to add a red label with the text "broken" to a card involves creating a label with those properties at the board level and then assigning it to a card.

The vision for this project is to have the library abstract away this kind of complication from the user.

A solid design needs to be outlined where a user can not only assign labels by ID, but also be able to just say assign a label of X color with Y text, and the library will do the work to find out if such a label already exists at the board level, creating it if necessary before assigning it to the card.