pre-alpha colormap()

Not ready for use except by the author.
colorize (broken check)
colormapAlpha() and colorizeAlpha() added
colormap doc
colormaps
rescale doc improved
colorize() rename arg to 'col' to match rest of R
colorize: fix code-doc mismatch
colormap() loses 'file' arg (subsumed into 'name')
colormap() now handles method 2
colormap/colorize get missingColor arg
colorize and colormap manpage speedup
colormap misses top bin in last help example
Merge branch 'issue432' into colorize
start work on new Colormap fcn (just skeleton)
start docs on Colormap (fcn does nothing yet)
Colormap() halfway working
Colormap() clean up docs a bit
434 fixed
Colormap as on blog