By Manuel Ortiz Esc&aacute;mez New America Media MEXICO CITY &mdash; &nbsp;Thousands of people &mdash; convened by the Mexican poet Javier Sicilia, whose son was recently murdered &mdash; marched here to demand that the government and organized crime groups end the brutal violence gripping the country. &nbsp;&nbsp;&nbsp; The protesters &mdash; made up of students, Central American [...]