Test filesystem provides symlink in autogen.sh (closes #414)

Author: stephane

autogen.sh

@@ -1,5 +1,10 @@
 #! /bin/sh
-if autoreconf --install --symlink --force; then
+do_symlink=
+if ln -s autogen-symlink-test autogen-symlink-test-link > /dev/null 2>&1; then
+    do_symlink=--symlink
+    rm autogen-symlink-test-link
+fi
+if autoreconf --install $do_symlink --force; then
 	echo
 	echo "------------------------------------------------------"
 	echo "Initialized build system. You can now run ./configure "