By Katie Kerwin McCrimmon Im blaming Francis Underwood. The soulless snake responsible for all evil in the nations Capitol on the Netflix hit, House of Cards, turned me into a couch potato this winter. Oh, and those Crawley sisters on Downton Abbey also messed up my metabolism. I was late to that party, so my daughter and I binged on three seasons of love, war and class intrigue, galloping from the sinking of the Titanic through World War I to the Roaring Twenties in a matter of weeks. Im a health writer so I try to monitor my wellness in…