Update shell code

Now it (mostly) passes shellcheck and is formatted with shfmt.

framework/shims/npm

@@ -2,14 +2,12 @@
 
 set -eu
 
-DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+npm_shim_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+export npm_shim_DIR
 
-source "$DIR"/node.common
+# shellcheck source=node.common
+source "$npm_shim_DIR"/node.common
 
-cd $DIR/../.nodejs-config
-echo in dir $(pwd)
+cd "$npm_shim_DIR"/../.nodejs-config
+echo in dir "$(pwd)"
 npm "$@"
-
-
-
-