FEAT: support openhermes 2.5

[Bojun-Feng]

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For the past few months I have been hearing awesome things about the OpenHermes 2.5 model as one of the best 7B models that can outperform much larger models, especially in the r/LocalLlama community. Every week there is a new post about its capabilities.

I downloaded the Q2_K model and was very surprised (pleasantly) by its performance. Among all the 7B Q2_K models I have tried, this definitely has the best performance. It also fits inside my 8GB RAM laptop, which is another plus. I'll made a PR to integrate it into our repo.

Some Sources include:

• Link to Post (History Screenshot)

I find it does summaries quite well, I have asked it about a wide range of topics and it has been ~90% correct on the first response, and can kind of fall apart after going back and forth a few times, but it's only 7b.

• Link to Post (History Screenshot)

I'll go ahead and say OpenHermes 2.5 is the best 7b model I used so far. You can say it's llama 65B and people wouldn't know.

• Link to Post (History Screenshot)

I simply tallied the number of thumbs-ups I gave for each first (👍👍👍), second (👍👍), and third place (👍) in all three tests series - which gives us this final ranking:

1st. 👍👍👍👍👍👍👍 OpenHermes-2.5-Mistral-7B with official ChatML format
...
All three models are excellent, they're definitely the three best 7B models so far by far.