Add Automagic v2 optimizer. It uses significantly less vram and is much more efficient.

toolkit/optimizer.py

@@ -97,6 +97,9 @@ def get_optimizer(
     elif lower_type == 'automagic':
         from toolkit.optimizers.automagic import Automagic
         optimizer = Automagic(params, lr=float(learning_rate), **optimizer_params)
+    elif lower_type == 'automagic2':
+        from toolkit.optimizers.automagic2 import Automagic2
+        optimizer = Automagic2(params, lr=float(learning_rate), **optimizer_params)
     else:
         raise ValueError(f'Unknown optimizer type {optimizer_type}')
     return optimizer