SearXNG (priv.au) wót zeraye

Add SearXNG to search engine list with https://priv.au/ hosting.

SearXNG is a free internet metasearch engine which aggregates results from various search services and databases. Users are neither tracked nor profiled. For more see: https://github.com/searxng/searxng

Source code: https://github.com/zeraye/searxng-firefox-extension

If something is broken, let me know: zeraye@protonmail.com