Turn the combining of scripts into a function

src/freedombone-image-make

-#!/bin/sh
+#!/bin/bash
 #
 # .---.                  .              .
 # |                      |              |
 export TEXTDOMAIN=${PROJECT_NAME}-image-make
 export TEXTDOMAINDIR="/usr/share/locale"
 
+PROJECT_INSTALL_DIR=/usr/local/bin
+if [ -f /usr/bin/${PROJECT_NAME} ]; then
+	PROJECT_INSTALL_DIR=/usr/bin
+fi
+source $PROJECT_INSTALL_DIR/${PROJECT_NAME}-vars
+
 #set -x # Enable debugging
 
 IMAGE=$1
 TEMP_CUSTOMISE4=/tmp/${PROJECT_NAME}-image-customise4
 
 # cat all the things together
-cp $PROJECT_INSTALL_DIR/${PROJECT_NAME}-vars $TEMP_CUSTOMISE2
-echo $'Adding utilities to customised customisation script'
-UTILS_FILES=/usr/share/${PROJECT_NAME}/utils/${PROJECT_NAME}-utils-*
-for f in $UTILS_FILES
-do
-  cat $f >> $TEMP_CUSTOMISE2
-done
-echo $'Adding base system to customised customisation script'
-BASE_SYSTEM_FILES=/usr/share/${PROJECT_NAME}/base/${PROJECT_NAME}-base-*
-for f in $BASE_SYSTEM_FILES
-do
-  cat $f >> $TEMP_CUSTOMISE2
-done
-echo $'Adding apps to customised customisation script'
-APP_FILES=/usr/share/${PROJECT_NAME}/apps/${PROJECT_NAME}-app-*
-for f in $APP_FILES
-do
-  cat $f >> $TEMP_CUSTOMISE2
-done
-echo $'Removing headers from customised customisation script'
-sed -i 's|#!/bin/bash||g' $TEMP_CUSTOMISE2
+combine_all_scripts $TEMP_CUSTOMISE2
+if [ ! -f $TEMP_CUSTOMISE2 ]; then
+	echo $'Could not combine scripts'
+	exit 627219
+fi
 
 echo $'Changing values within customised customisation script'
 cp $PROJECT_INSTALL_DIR/${PROJECT_NAME}-image-customise $TEMP_CUSTOMISE3

src/freedombone-utils-setup

 	install_apps
 }
 
+function combine_all_scripts {
+	combined_filename=$1
+
+	# initial variables
+	cp $PROJECT_INSTALL_DIR/${PROJECT_NAME}-vars $combined_filename
+
+	# utilities
+	UTILS_FILES=/usr/share/${PROJECT_NAME}/utils/${PROJECT_NAME}-utils-*
+	for f in $UTILS_FILES
+	do
+		# this removes the first line, which is #!/bin/bash
+		tail -n +2 "$f" >> $combined_filename
+	done
+
+	# base system
+	BASE_SYSTEM_FILES=/usr/share/${PROJECT_NAME}/base/${PROJECT_NAME}-base-*
+	for f in $BASE_SYSTEM_FILES
+	do
+		tail -n +2 "$f" >> $combined_filename
+	done
+
+	# apps
+	APP_FILES=/usr/share/${PROJECT_NAME}/apps/${PROJECT_NAME}-app-*
+	for f in $APP_FILES
+	do
+		tail -n +2 "$f" >> $combined_filename
+	done
+}
+
 # NOTE: deliberately no exit 0