feat: Ability to set additional inference parameters such as top_p and num_ctx

[sammcj]

It would be great if you could set common inference parameters such as top_p and num_ctx.

• top_p helps control quality vs creativity (much smarter than temperature)
• min_p another, newer algorithm for quality vs creativity (some would argue even smarter than top_p)
• num_ctx configures what context size to load the model with
• repetition_penalty configures how much repetition is allowed in the generations (this is an oversimplification but it's useful)

I think they're the most commonly used parameters, however a complete list is available https://github.com/ollama/ollama/blob/main/docs/modelfile.md#valid-parameters-and-values