Adding linenoise.cpp to llama-run

This is a fork of linenoise that is C++17 compatible. I intend on
adding it to llama-run so we can do things like traverse prompt
history via the up and down arrows:

https://github.com/ericcurtin/linenoise.cpp

Signed-off-by: Eric Curtin <[email protected]>

Author: ericcurtin