Find and exec vvv-init.sh before finding vvv-nginx.conf

The vvv-init.sh script may in fact generate vvv-nginx.conf files on the fly.
Inline auto-site-setup so init-generated vvv-hosts can be found
Accomodate server directives that have hundred(s) of server_names

For example large multisite networks.

This change enables a network with 179 server_names.
Increase auto-site-setup seach depth from 4 to 5
Merge pull request #199 from x-team/init-then-nginx-conf

Allow vvv-init.sh to generate vvv-hosts and vvv-nginx.conf, etc