simplified ISABELLE_HOME on Windows (see also 9c8a1b9c0630, 5a7903ba2dac);

--- a/lib/scripts/getsettings	Sat Sep 28 13:40:33 2013 +0200
+++ b/lib/scripts/getsettings	Sat Sep 28 13:50:38 2013 +0200
@@ -23,9 +23,6 @@
     USER_HOME="$(cygpath -u "$HOMEDRIVE\\$HOMEPATH")"
   fi
 
-  ISABELLE_HOME_WINDOWS="$(cygpath -w "$(dirname "$ISABELLE_HOME")")\\$(basename "$ISABELLE_HOME")"
-  ISABELLE_HOME="$(cygpath -u "$ISABELLE_HOME_WINDOWS")"
-
   function jvmpath() { cygpath -i -C UTF8 -w -p "$@"; }
   CYGWIN_ROOT="$(jvmpath "/")"
 

--- a/src/Pure/Tools/main.scala	Sat Sep 28 13:40:33 2013 +0200
+++ b/src/Pure/Tools/main.scala	Sat Sep 28 13:50:38 2013 +0200
@@ -133,7 +133,7 @@
       try {
         GUI.init_laf()
 
-        val isabelle_home0 = System.getenv("ISABELLE_HOME_WINDOWS")
+        val isabelle_home0 = System.getenv("ISABELLE_HOME")
         val isabelle_home = System.getProperty("isabelle.home")
 
         if (isabelle_home0 == null || isabelle_home0 == "") {