enh: Fix shellcheck warnings

Author: davidhcefx

tool/include-list-gen.sh

@@ -1,9 +1,9 @@
 #!/bin/sh -e
 # Generate the content of nanorc
 
-base="$(dirname $0)/../"
+base="$(dirname "$0")/../"
 
 rm "$base/nanorc"
-for n in $base/*.nanorc; do
+for n in "$base"/*.nanorc; do
     printf 'include "~/.nano/%s"\n' "$(basename "$n")" >> "$base/nanorc"
 done

tool/shellcheck.sh

@@ -1,5 +1,5 @@
 #!/bin/sh -ev
 # Shellcheck the script
 
-base="$(dirname $0)/../"
+base="$(dirname "$0")/../"
 shellcheck "$base/install.sh"