Actress Brooke Shields— known for her Calvin Klein Jeans modeling in the ‘80s as well as for her role as Emmeline in “The Blue Lagoon” — is launching a new hair care line.   Dropping this June, the line is formulated for women over 40. It will address thinning hair, scalp health and collagen loss.     The line, called Commence, will share the same ethos as her separate venture, Beginning Is Now, an online community Shields initiated for the same demographic.    ...