Library updates

• llama-cpp-python: bump to 0.2.82.
• ExLlamaV2: bump to 0.1.7 (adds Gemma-2 support).

Changes

• Add new --no_xformers and --no_sdpa flags for ExLlamaV2.
  • Note: to use Gemma-2 with ExLlamaV2, you currently must use the --no_flash_attn --no_xformers --no_sdpa flags, or check the corresponding checkboxes in the UI before loading the model, otherwise it will perform very badly.
• Minor UI updates.