small updates to some text files

doc/TITLE_x_SYS.txt

@@ -8,6 +8,9 @@ Palettes are stored first, there's space for 45 of them ($5A0 bytes).
 Following that are 45 sprite tiles in the regular SPR file format, making a 9*5
 tiles (144*80 pixels) logo. Tiles are mapped from left to right, top to bottom.
 
+Palette note: Index 0 is transparent, and the area behind the game logo in
+the CDZ menu screen is not entirely black. Proceed with caution.
+
 todo: Create a tool that can generate a TITLE_*.SYS file from a .SPR file and
 various .ngpal files. (blastar's NGFX can import from BMP/PNG/GIF files)
 

doc/functions/palette/pal_actions.txt

@@ -3,6 +3,9 @@ freemlib for Neo-Geo - Palette Actions
 Palette actions are in charge of handling effects for sections of the palette.
 This is different from full-palette effects (e.g. fading).
 
+"(You really should just load a pre baked palette entry instead of computing it)"
+- hpman, https://wiki.neogeodev.org/index.php?title=Palette_rotation&oldid=5087
+
 (Usage)
 Trying to figure out the best way to handle this...
 palAction_Handler runs through the Palette Action buffer every frame.

doc/notes.txt

@@ -19,5 +19,5 @@ flipped between the two architectures.
 
 e.g. Loading an 8-bit value from one register to another:
 (68K) move.b source,dest
-(Z80) ld	dest,source
+(Z80) ld     dest,source
 

doc/palette.txt

@@ -37,8 +37,10 @@ Blue	000001
 The full range of color values for each channel is 00-3F.
 
 Warning: the following RGB values are approximations due to the fact that a
-resistor network is used to modify the actual color values. See MAME source for
-more information.
+resistor network is used to modify the actual color values.
+
+See MAME source for more information:
+https://github.com/mamedev/mame/blob/master/src/mame/video/neogeo.cpp
 
 RGB #FFFFFF = Neo-Geo $7FFF
 RGB #FEFEFE = Geo-Geo $FFFF