John Brown is a fascinating figure. Depending on where you grew up, you were taught either that he was a misguided freedom fighter or an irredeemable terrorist. (I went to school in Virginia, so I learned the latter.) The truth is somewhere in between — he was indeed a domestic terrorist, but he was also a man on the right side of history who recognized that bloody revolution was the only way to end slavery in America. The Good Lord Bird, a Showtime limited series premiering this week, attempts to paint a humanizing picture of the infamous abolitionist, and it succeeds …