using copy function instead of copy method
including group_lasso_epigraphs in the API
found a bug in the projection onto the epigraph -- when norm + cut is negative, should have been returning 0
default offset value
whitespace change
avoiding divide by 0
specifying weighted_atoms without a shape
starting to work on other tests
fix of weighted_atom signature, change Solver repr so that we might call it based on its repr