Ask to renew git configurations after installation

#180

install.bash

@@ -50,6 +50,15 @@ main() {
         copy ${0%/*} ${INSTALL_PATH}
     fi
     echo "'elegant git' is installed to '${INSTALL_PATH}/bin/git-elegant'."
+    echo "
+The final step after installation is to run
+    git elegant acquire-repository
+for each git repository where Elegant Git is going to be used.
+
+If this step is not completed, Elegant Git may behave unexpectedly
+since the desired Git configuration (relevant for the current version)
+is not applied.
+"
     command -v git-elegant 1>/dev/null 2>&1 || next-steps ${INSTALL_PATH}
 }