[WHO] Implement The Fourth Doctor

[padfoothelix]

Part of #10653 .

Card was tested and seems to work as intended.

Code was adapted from PlayFromTopOfLibraryEffect and [[Johann, Apprentice Sorcerer]]. The tests in those cards are not exactly the same ; I took a maximalist approach but I'm not sure they are all necessary. Also not certain how the MageIdentifier class works ; I copied code from Johann. Finally, the reflexive ability is fired from the applies method ; I'm not sure if this is a proper way to do it. Then again, it works.

Thanks for your work !

[padfoothelix]

I believe I have found a better way to code this. Don't bother reviewing it, I'll update it soon.

[padfoothelix]

Here is another proposition based on [[Serra Paragon]]. Card was tested and works as expected.

[github-actions[bot]]

Serra Paragon - (Gatherer) (Scryfall) (EDHREC)

{2}{W}{W} Creature — Angel 3/4 Flying Once during each of your turns, you may play a land from your graveyard or cast a permanent spell with mana value 3 or less from your graveyard. If you do, it gains "When this permanent is put into a graveyard from the battlefield, exile it and you gain 2 life."

[padfoothelix]

Requested changes have been implemented. Card was tested again and seems to work fine.