added in conf and supported by code:
- AuthenticationMethod: (empty)/basic/proxy: Supporting basic/proxy
authentication methods
- AuthUserHeader: when AuthenticationMethod is proxy, name of header
with username
- PowerAuthUsers: when AuthenticationMethod is proxy, liast of power
users 
- AuditLogFile: name of textfile to audit (disabled when empty)
- ListenAddress: address to listen on (e.g. can be restircted to local
connections in "127.0.0.1:3000" or open to all in ":3000")

api:
- supporting read-only/power users notion. Every manipulating operation
is checked for auth user (applies only on AuthenticationMethod="proxy")