FEATURE: implement parallel tool calling and update vision support

[merefield]

• FEATURE: Adds new open ai model gpt-4-turbo which has vision support
• FEATURE: Implements parallel tool calling so LLM can now call multiple tools in one cycle!
  • COMPATIBILITY: this removes legacy function format
• IMPROVE: Speeds up and reduces cost of RAG mode by eliminating one call to the LLM per interaction. This translates potentially to reducing the cost of RAG mode by ~40%!
• IMPROVE: Improves Chatbot vision support by giving you the choice to enable it but use it just as a function to save funds
• FIX: RAG mode bot wasn't respecting call parameters!