Support for bitmaps in 8-bit arrays

[rangeTonic]

Bitmaps encoded in 16 bit unsigned short arrays produce one garbage byte in memory per 2 pixels:

0000RRRR GGGGBBBB,  0000RRRR GGGGBBBB,  0000RRRR GGGGBBBB ...

As an alternative, bitmaps can be stored in 8 bit arrays instead, like this:

RRRRGGGG,  BBBBRRRR,  GGGGBBBB,  RRRRGGGG, BBBBRRRR,  GGGGBBBB ...