1) Fix last commit.  Crashes/Video corruption resolved.
2) Add ccputs() and cputch() to ciolib.  These take a colour value as their
   first argument, which is a palette entry.  They otherwise work the same
   as their counterpart without the c prefix.
3) Add a flags member to vstat which needs to be set before loading a mode.
   The only defined flag is currently VIDMODES_FLAG_PALETTE_VMEM.
4) If VIDMODES_FLAG_PALETTE_VMEM is set, allocate 32-bit arrays for the
   foreground and background palette entries for each cell.
5) Have bitmap_con.c use the palette vmem flag.
6) Have movetext() copy the palette entries along with the regular vmem.

In theory now, bitmap_con.c will handle giant colour palettes, and anything
that uses movetext() (ie: scrolling) will maintain the colours.

gettext() and puttext() unfortunately can not access the palette memory...
we'll see if we need extended replacements for them or not.