v0.8.0

• Added pyproximal.projection.L01BallProj and pyproximal.proximal.L01Ball operators
• Added eta to pyproximal.optimization.primal.ProximalGradient
• Added eta and weights to pyproximal.optimization.primal.GeneralizedProximalGradient
• Allow eta to pyproximal.optimization.primal.ProximalGradient to have iteration-dependent epsg
• Switched from lsqr to cg in pyproximal.projection.AffineSetProj