Implement optimizers

[kozistr]

• implement Accelerated SGD optimizer
• implement Adaptive SGD optimizer
• implement A2Grad optimizer (3 variants)
• implement Yogi optimizer
• implement AdaMod optimizer
• implement PID optimizer
• implement AggMo optimizer
• implement QHAdam optimizer
• implement QHM optimizer
• implement SGDW optimizer
• implement SWATS optimizer
• implement Fromage optimizer
• implement MSVAG optimizer