Generate per-language translation sources (#806)

This generates dedicates Translation.cpp files for translation language
and derives all language-specific data from them.

The Makefile is extended to also take care of generating these source
files.
This allows reuse of nearly all object files between builds of different
languages for the same model and regenerating the translation sources if
necessary.
This speeds up the release builds and the normal write-compile-cycle
considerably.
It also eliminates miscompilations when manually building different
languages.

source/build.sh

@@ -123,16 +123,8 @@ if [ ${#BUILD_LANGUAGES[@]} -gt 0 ] && [ ${#BUILD_MODELS[@]} -gt 0 ]; then
     checkLastCommand
 
     for model in "${BUILD_MODELS[@]}"; do
-        for lang in "${BUILD_LANGUAGES[@]}"; do
-            echo "Building firmware for $model in $lang"
-            make -j lang="$lang" model="$model" >/dev/null
-            checkLastCommand
-            echo "Cleanup Temp files for $model in $lang"
-            rm -rf Objects/*/Core/ >/dev/null
-            checkLastCommand
-        done
-        echo "Cleanup model change"
-        rm -rf Objects/ >/dev/null
+        echo "Building firmware for $model in ${BUILD_LANGUAGES[@]}"
+        make -j$(nproc) model="$model" "${BUILD_LANGUAGES[@]/#/firmware-}" >/dev/null
         checkLastCommand
     done
 else