moved everything to different stages

stage/prechroot/bison.bash

@@ -0,0 +1,22 @@
+
+fetch $BISON_URL
+
+sudo chroot "$SYSROOT" /usr/bin/env -i \
+	MAKEFLAGS="$MAKEFLAGS" \
+	PATH=/usr/bin:/usr/sbin \
+	SOURCES=/sources \
+	BISON_VERSION=$BISON_VERSION \
+	/usr/bin/bash <<- "EOF"
+		set -euo pipefail
+
+		cd "$SOURCES" && tar xf bison-$BISON_VERSION.tar.xz && cd bison-$BISON_VERSION
+
+		./configure \
+			--prefix=/usr \
+			--silent \
+			--quiet
+		
+		make && make install
+
+		cd "$SOURCES" && rm -rf bison-$BISON_VERSION
+EOF