/*
 * Monitor a collection.
 *
 * Aliases:
 *   Fam::Collection#monitor_col
 *   Fam::Collection#col
 *
 * Examples:
 *   req = fam.monitor_col 'download/images', 1, '*.jpg'
 *
 */
static VALUE fam_conn_col(VALUE self, VALUE col, VALUE depth, VALUE mask) {