This change does away with separate attributes foreground and background,
opting for an array of color "aspects", where the aspect can vary
over an enum which can either be FOREGROUND or BACKGROUND. This will allow
writing a single set of color-editing code which can work either on the
foreground or background color of a cell.
Now palettes are allocated and deallocated in fteapot as well as teapot;
both executables have some color rendering, with fteapot using the cell
foreground and background (there's just no way to set them at the moment).
teapot is so far only using color in the header.
Implements #39.
So far, this jst consists of initializing color in curses mode, and making
the display start and end part of intializing and freeing a sheet (so that
it can control allocating the palette, for example, where the data structure
used depends on what kind of display it is.
Next up will be to allocate and destroy the color palette, and set up the
default colors for cells to use (0 for foreground,
TEAPOT_WHITE for background.) The outline beyond that is to allow setting of
the cell colors, then actually display those colors, and finally edit the
palette.
Glen Whitney