Expected problems:

* library reduction

  It is difficult to reduce a library if you don't know what functions
  in it will be used.  Since additional modules could be dropped onto
  install media at any time, it is very difficult to guarantee that a
  reduced libc will have all the symbols they need.

  The least insane way of handling this is probably to have a libc6
  package and other "full" packages with the libraries we need; this
  will waste some space, but is probably the only way to go for now.

* ramdisk size

  How big a ram disk do we need? What happens if the installer is asked to
  install just one more udeb onto a full ramdisk, and runs out of space?

  Possibilities: 
  	- ramfs (2.4 only)
  	- lvm/md on a ramdisk
	- create 1 mb ramdisks on the fly, and put the actual files in
	  there, symlinking to the real filesystem
	- similarly/complimentary, once other filesystems are available,
	  put the file on them (eg, on nfs, pre-unpacked on the cd we are
	  installing from, in a spare disk partition).