contribute fluent log builder

[pwelter34]

Writing info message via fluent API.

_logger.Info()
    .Message("This is a test fluent message '{0}'.", DateTime.Now.Ticks)
    .Property("Test", "InfoWrite")
    .Write();

Writing error message.

try
{
    string text = File.ReadAllText(path);
}
catch (Exception ex)
{
    _logger.Error()
        .Message("Error reading file '{0}'.", path)
        .Exception(ex)
        .Property("Test", "ErrorWrite")
        .Write();
}