By Daniel Wiessner (Reuters) – The U.S. Department of Labor on Tuesday unveiled a proposal that would make it harder for companies to treat workers as independent contractors, potentially upending the gig economy and other industries that rely heavily on contract labor. The line between when a worker is considered a company’s employee, who is entitled to various legal protections, or an independent contractor has shifted over the last decade, as businesses have faced an increasing number of lawsuits by workers who claim they were misclassified. WHY IS WORKER CLASSIFICATION IMPORTANT? Most fede…