MEDIUM: log: New format-log flags: %Fi %Fp %Si %Sp %Ts %rt %H %pid

MEDIUM: log: New format-log flags: %Fi %Fp %Si %Sp %Ts %rt %H %pid

%Fi: Frontend IP
%Fp: Frontend Port
%Si: Server IP
%Sp: Server Port
%Ts: Timestamp
%rt: HTTP request counter
%H: hostname
%pid: PID

+X: Hexadecimal represenation

The +X mode in logformat displays hexadecimal for the following flags
%Ci %Cp %Fi %Fp %Bi %Bp %Si %Sp %Ts %ct %pid

rename logformat_write_string() to lf_text()

Optimize size computation