This now uses the getline function to receive the header, replacing
read_line_buffer, which has been deleted since it is otherwise unused.
Furthermore, once the protocol has been determined, the current status
is handled immediately to be shown (though this has not been added for
the i3bar protocol since it has not yet been rewritten to handle this).
Escape line return when reading from a file with the '\' character.
Similar to shell scripts.
Signed-off-by: Roosembert Palacios <roosembert.palacios@epfl.ch>
