Spelling/grammar fixes for ch 2, 4, 5, 6

[elijah-tai]

Fixes:

• Chapter 2 (PyMC3): typo in "prior distributions" in last paragraph of "A Simple Case"
• Chapter 4 (PyMC3): typo in Law of Large Numbers Example - "... is equal to it's parameter." (it's --> its)
• Chapter 4 (PyMC3): “Our intuition should tell us that the counties with the most extreme population heights should also be uniformly spread over 100 to 4000” (4000 --> 1500)
• Chapter 4 (PyMC2 and PyMC3): #adding a number to the end of the %run call _with_ get the ith top photo (with --> will, photo --> post)
• Chapter 5 (PyMC2 and PyMC3): "This loss function might be used by a political pundit who's job requires him or her to give confident "Yes/No" answers.” (who’s —> whose)
• Chapter 6 (PyMC3): "... suggesting that it's true daily return is negative ..." (it's --> its)

Thanks for the read!

[CamDavidsonPilon]

❤️ nice! Thanks @itselijahtai

[elijah-tai]

My pleasure @CamDavidsonPilon