Not everyone is happy Jimmy Fallon messed with Donald Trump's hair

Donald Trump's hair has been a comedic gold mine for late-night talk show hosts since ... well, pretty much forever.
On Thursday, Jimmy Fallon got to touch it on The Tonight Show. 
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Fallon asked the Republican presidential nominee — fresh off visiting Dr. Oz and terrifying a little girl in Flint, Michigan — if he could touch his hair. 
Trump paused, apologized to the people of New Hampshire (wher