Leela Zero 0.17 + AutoGTP v18

• Implemented batching for GPUs, increasing speed.
• Added support for Tensor Cores on NVIDIA cards.
• Optimized Winograd code for CPU and GPU.
• Improved UCT formula.
• Improved root move selection by using Lower Confidence Bounds.
• Improved passing heuristics (disabled in self-play).
• Improved autotuner behavior in edge cases.
• The training code now supports mixed precision fp32/fp16 training.
• AutoGTP can now start from an arbitrary SGF position.
• AutoGTP can now play matches with different white/black parameters.
• AutoGTP can now send initial commands to the engine.
• AutoGTP now provides the full engine options in the SGF comments.
• AutoGTP now uses batching during self-play.
• GTP: Add support for gomill-explain_last_move.
• GTP: lz-analyze and lz-genmove_analyze now support an avoid tag.
• GTP: lz-analyze and lz-genmove_analyze now support a minmoves tag.
• GTP: lz-analyze and lz-genmove_analyze now support a (post) interval tag.
• GTP: loadsgf and printsgf can now save and load time control information.
• Bugfix: lz-setoption name playouts now works correctly.
• Bugfix: in analysis mode, provide output even if we did not have to search.
• Bugfix: detect if the weights file is for the wrong board format.
• Bugfix: bail out if OpenCL doesn't find a GPU (instead of using OpenCL-on-CPU).