Move specialized plotter classes from plotter.h to specific plotter_xx.h

plotter.h contains now only a header common to all plotters.
The code does not actually change, but it allows modifying a specific plotter
without recompiling most of kicad files.

common/plotters/PDF_plotter.cpp

@@ -32,7 +32,6 @@
 #include <eda_base_frame.h>
 #include <base_struct.h>
 #include <common.h>
-#include <plotter.h>
 #include <macros.h>
 #include <wx/zstream.h>
 #include <wx/mstream.h>
@@ -40,6 +39,9 @@
 
 #include <algorithm>
 
+#include "plotters_pslike.h"
+
+
 
 std::string PDF_PLOTTER::encodeStringForPlotter( const wxString& aText )
 {