Always crebuild the rmc-lib to avoid problems when compiler upgrades (rust-lang#649)

Author: danielsn

scripts/setup/build_rmc_lib.sh

@@ -10,5 +10,6 @@ SCRIPTS_DIR="$(dirname $SCRIPT_DIR)"
 REPO_DIR="$(dirname $SCRIPTS_DIR)"
 
 export RUSTC=$(${SCRIPTS_DIR}/rmc-rustc --rmc-path)
+cargo clean --manifest-path "${REPO_DIR}/library/rmc/Cargo.toml" $@
 cargo build --manifest-path "${REPO_DIR}/library/rmc/Cargo.toml" $@