Modify build-script include folder keys

The key for getting the path of  the own module in the includes.txt is
no  longer '{self}', but rather '{module}', as that is a little easier
to understand.

modules/assets/includes.txt

@@ -1,3 +1,3 @@
-{self}/inc-c
+{module}/inc-c
 {module-folder}/utility/inc-c
 {module-folder}/ecs/inc-c

modules/ecs/includes.txt

@@ -1,2 +1,2 @@
-{self}/inc-c
+{module}/inc-c
 {module-folder}/utility/inc-c

modules/renderer/includes.txt

@@ -1,4 +1,4 @@
-{self}/inc-c
+{module}/inc-c
 {module-folder}/utility/inc-c
 {module-folder}/window/inc-c
 {module-folder}/ecs/inc-c

modules/utility/includes.txt

@@ -1 +1 @@
-{self}/inc-c
+{module}/inc-c

modules/window/includes.txt

@@ -1,3 +1,3 @@
-{self}/inc-c
+{module}/inc-c
 {module-folder}/utility/inc-c
 {module-folder}/ecs/inc-c

modules/world/includes.txt

@@ -1,2 +1,2 @@
-{self}/inc-c
+{module}/inc-c
 {module-folder}/utility/inc-c

scripts/build.bash

@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 
 cd $(dirname $0)
 SCRIPT_PATH=$(pwd)
@@ -42,7 +43,7 @@ function make_include_statements() {
 
     for INCLUDE_PATH in $(cat modules/$MODULE_NAME/includes.txt)
     do
-        MODIFIED_PATH="${INCLUDE_PATH//"{self}"/"$PROJECT_PATH/modules/$MODULE_NAME"}"
+        MODIFIED_PATH="${INCLUDE_PATH//"{module}"/"$PROJECT_PATH/modules/$MODULE_NAME"}"
         MODIFIED_PATH="${MODIFIED_PATH//"{module-folder}"/"$PROJECT_PATH/modules"}"
         echo "-I ${MODIFIED_PATH//"{dependencies}"/"$PROJECT_PATH/dependencies"}"
     done
@@ -68,7 +69,14 @@ function build_single_module() {
         gcc -c -o .build/modules/$MODULE_NAME/objects/$OBJECT_NAME -g3 modules/$MODULE_NAME/src-c/$SOURCE $INCLUDE_STATEMENTS
     done
 
+    if [[ $(ls .build/modules/$MODULE_NAME/objects/ | grep ".o$") == "" ]];
+    then
+        echo "> Empty Module, not creating archive."
+        echo " "
+        return
+    fi
     ar -rvs .build/archives/voxula-$MODULE_NAME.a .build/modules/$MODULE_NAME/objects/*.o
+    echo " "
 }
 
 mkdir -p .build/archives