The man accused of killing seven people at a July Fourth parade in Highland Park last year fired his public defenders Monday and said he plans to represent himself at trial, slated to start in February.Robert E. Crimo III is charged with 21 counts of first-degree murder, 48 counts of attempted murder and 48 counts of aggravated battery for the shooting. Dozens, including children, were injured.Several times, Judge Victoria A. Rossetti asked if Crimo understood the possible penalties — including consecutive life …