FRANKFURT (Reuters) - Germany's Bayer is close to agreeing a settlement over claims its glyphosate-based Roundup weedkiller causes cancer this week, two people familiar with the matter told Reuters.Some details and the overall settlement amount have yet to be hammered out in the final stage of talks, one of the sources said.German business daily Handelsblatt earlier reported a deal was imminent, with Bayer pledging $8-10 billion (£6.4-8 billion) to settle the claims, including a $2 billion..