Fix colour emphasis support for NTSC filter & raw palette + nes decoder shader

- this implementation is based on a more accurate colour emphasis from fceux.

- The raw palette + nes decoder shader was kinda incomplete since the implementation was based on
a per-frame basis which means that the emphasis bits were read once and applied to the whole frame. This
means that some games that uses a per pixel or per scanline emphasis would not appear correct. The more
accurate implementation reads emphasis bits from bits 5-7 of PPU[1] and saves this info in a separate frame.

- The same implementation is also used to fix emphasis for the ntsc filter.

src/ntsc/nes_ntsc.h

@@ -61,8 +61,8 @@ In_row_width is the number of pixels to get to the next input row. Out_pitch
 is the number of *bytes* to get to the next output row. Output pixel format
 is set by NES_NTSC_OUT_DEPTH (defaults to 16-bit RGB). */
 void nes_ntsc_blit( nes_ntsc_t const* ntsc, NES_NTSC_IN_T const* nes_in,
-		long in_row_width, int burst_phase, int in_width, int in_height,
-		void* rgb_out, long out_pitch );
+		NES_NTSC_IN_T const* nes_inD, long in_row_width, int burst_phase, int in_width,
+		int in_height, void* rgb_out, long out_pitch );
 
 /* Number of output pixels written by blitter for given input width. Width might
 be rounded down slightly; use NES_NTSC_IN_WIDTH() on result to find rounded