build: rename option(s) to package(s).

Most GNU Boot users are interested in running GNU/Linux or BSD
operating systems. And the way to install software on these
operating systems is through a package manager. So most users and
contributors already know the package manager abstraction.

So referring to packages instead of options makes it easier to
understand what the script is doing.

Signed-off-by: Denis 'GNUtoo' Carikli <GNUtoo@cyberdimension.org>
Acked-by: Adrien 'neox' Bourmault <neox@gnu.org>

build

@@ -36,15 +36,15 @@ listmodes() {
 }
 
 # Takes exactly one mode as parameter
-listoptions() {
-	for option in "${build}"/"${1}"/*; do
-		printf '%s\n' "${option##*/}"
+list_packages() {
+	for package in "${build}"/"${1}"/*; do
+		printf '%s\n' "${package##*/}"
 	done
 }
 
 help() {
 	cat <<- EOF
-	USAGE:	./build <MODE> <OPTION>
+	USAGE:	./build <MODE> <PACKAGE>
 
 	possible values for 'mode':
 	$(listmodes)
@@ -77,26 +77,26 @@ fi
 
 if [ $# -gt 1 ]; then
 
-	option="${2}"
+	package="${2}"
 	shift 2
 
-	case "${option}" in
+	case "${package}" in
 		list)
-			printf "Available options for mode '%s':\n\n" "${mode}"
-			listoptions "${mode}"
+			printf "Available packages for mode '%s':\n\n" "${mode}"
+			list_packages "${mode}"
 			;;
 		all)
-			for option in $(listoptions "${mode}"); do
-				"${build}"/"${mode}"/"${option}" $@
+			for package in $(list_packages "${mode}"); do
+				"${build}"/"${mode}"/"${package}" $@
 			done
 			;;
 		*)
 			if [ -d "${build}"/"${mode}"/ ]; then
-				if [ -f "${build}"/"${mode}"/"${option}" ]; then
-					"${build}"/"${mode}"/"${option}" $@
+				if [ -f "${build}"/"${mode}"/"${package}" ]; then
+					"${build}"/"${mode}"/"${package}" $@
 				else
 					help
-					die "Invalid option for '${mode}'." \
+					die "Invalid package for '${mode}'." \
 					    " See './build ${mode} list'."
 				fi
 			else