Trainer cards

[isenor]

Introduce trainer cards. Each one probably adds something new entirely.

[isenor]

To clearly define the scope, this should be:

As a player, I want to be able play Potion trainer cards from my hand so that my Pokemon won't be knocked out as quickly.

When a potion trainer card is selected with "select hand n" the player sees actions which list all the pokemon that can be healed. Once a Pokemon is selected (and after confirmation), it is healed 30 hit points. The card is then removed from the player's hand and put into the discard pile.