feat: embedded model configurations, add popular model examples, refactoring (#1532)

* move downloader out

* separate startup functions for preloading configuration files

* docs: add popular model examples

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

* shorteners

* Add llava

* Add mistral-openorca

* Better link to build section

* docs: update

* fixup

* Drop code dups

* Minor fixups

* Apply suggestions from code review

Signed-off-by: Ettore Di Giacinto <mudler@users.noreply.github.com>

* ci: try to cache gRPC build during tests

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

* ci: do not build all images for tests, just necessary

* ci: cache gRPC also in release pipeline

* fixes

* Update model_preload_test.go

Signed-off-by: Ettore Di Giacinto <mudler@users.noreply.github.com>

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Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
Signed-off-by: Ettore Di Giacinto <mudler@users.noreply.github.com>