Minor tweaks

Attached is a patch to Feb2001 which does the following * flushes stderr when :set -h<size> and :set {+,-}98 is used. As is, the informational messages that's printed on stderr may not appear until later with some terminal & CRT combos. * allows the use of "~/" in :cd commands. ~/ is substituted with whatever the environment variable HOME contains. It doesn't do other forms of tilde expansion, but if there's interest I could always add support for ~login/ i.e., first tweak is a bugfix, the second is a feature tweak. BTW, is there a technical reason why toggling between Haskell98 and Hugs mode can only be done at startup time? --sigbjorn