start the debugger only if it was never started, else, reuse it

Modules/Debuggers/ProjectCenter/GDBWrapper.m

@@ -91,6 +91,11 @@
     }
 }
 
+- (BOOL)debuggerStarted
+{
+  return debuggerStarted;
+}
+
 - (void)setFont:(NSFont *)aFont
 {
   if (font != aFont)

Modules/Debuggers/ProjectCenter/PCDebugger.m

@@ -179,7 +179,8 @@ NSString *PCDBDebuggerStartedNotification = @"PCDBDebuggerStartedNotification";
 - (void) show
 {
   [debuggerWindow makeKeyAndOrderFront: self];
-  [self startDebugger];
+  if (![debuggerWrapper debuggerStarted])
+    [self startDebugger];
 }
 
 - (void) startDebugger

Modules/Debuggers/ProjectCenter/PCDebuggerWrapperProtocol.h

@@ -42,6 +42,8 @@
 - (PCDebugger *)debugger;
 - (void)setDebugger:(PCDebugger *)dbg;
 
+- (BOOL)debuggerStarted;
+
 - (void) runProgram: (NSString *)path
  inCurrentDirectory: (NSString *)directory
       withArguments: (NSArray *)array