Fixes simmetrica-app not showing graphs with the last received values
This commit moves static files, template file and configuration file
to/opt folder
Cross distro / os compatibility (/etc for linux, /usr/local/etc
for darwin and APPDATA for Windows) for configuration file removed.
It's moved to /opt/simmetrica/config/config.yml
(Still you can define different path, and it still finds config
file in current working directory)
Also fixes simmetrica web app can't finds static files and template
files in Linux