avoid force-yes with newer version of apt-get (heroku#51)

force-yes was deprecated with 1.1, and split up into three new options.
Keep the same behavior by enabling all 3 options when a newer version is
detected.

This should fix errors at install time, which are tripping up the
current tests.

Fixes heroku#16.

bin/compile

@@ -38,6 +38,13 @@ APT_SOURCELIST_DIR="$CACHE_DIR/apt/sources"   # place custom sources.list here
 APT_SOURCES="$APT_SOURCELIST_DIR/sources.list"
 APT_FILE_MANIFEST="${APT_FILE_MANIFEST:-Aptfile}"
 
+APT_VERSION=$(apt-get -v | awk 'NR == 1{ print $2 }')
+
+case "$APT_VERSION" in
+  0* | 1.0*) APT_FORCE_YES="--force-yes";;
+  *)         APT_FORCE_YES="--allow-downgrades --allow-remove-essential --allow-change-held-packages";;
+esac
+
 if [ -f $APT_CACHE_DIR/$APT_FILE_MANIFEST ] && cmp -s $BUILD_DIR/$APT_FILE_MANIFEST $APT_CACHE_DIR/$APT_FILE_MANIFEST ; then
   # Old Aptfile is the same as new
   topic "Reusing cache"
@@ -72,7 +79,7 @@ for PACKAGE in $(cat $BUILD_DIR/$APT_FILE_MANIFEST | grep -v -s -e '^#' | grep -
     curl -s -L -z $PACKAGE_FILE -o $PACKAGE_FILE $PACKAGE 2>&1 | indent
   else
     topic "Fetching .debs for $PACKAGE"
-    apt-get $APT_OPTIONS -y --allow-downgrades -d install --reinstall $PACKAGE | indent
+    apt-get $APT_OPTIONS -y $APT_FORCE_YES -d install --reinstall $PACKAGE | indent
   fi
 done