Switch to stashing our build artifacts in the stable kaleidoscope temp dir, rather than the source dir

This is particularly important for in-kaleidoscope-tree artifacts like
the examples.

If we build the examples and move the compiled artifacts into the
Kaleidoscope tree, even under examples, it busts arduino's core
compilation cache, adding an extra 10s to the next compilation.

Signed-off-by: Jesse Vincent <jesse@keyboard.io>

bin/kaleidoscope-builder

@@ -26,14 +26,13 @@ build_version () {
 }
 
 build_paths() {
-    OUTPUT_DIR="${OUTPUT_DIR:-output/${LIBRARY}}"
-    OUTPUT_PATH="${OUTPUT_PATH:-${SOURCEDIR}/${OUTPUT_DIR}}"
     STABLE_TEMP_DIR="${STABLE_TEMP_DIR:-/tmp/kaleidoscope-${USER}}"
+    BUILD_PATH="${BUILD_PATH:-${STABLE_TEMP_DIR}/sketch/${LIBRARY}}/build"
+    OUTPUT_PATH="${OUTPUT_PATH:-${STABLE_TEMP_DIR}/sketch/${LIBRARY}}/output"
     CCACHE_WRAPPER_DIR="${CCACHE_WRAPPER_DIR:-${STABLE_TEMP_DIR}/ccache/bin}"
     CORE_CACHE_PATH="${CORE_CACHE_PATH:-${STABLE_TEMP_DIR}/arduino-cores}"
     
 
-    BUILD_PATH="${BUILD_PATH:-${STABLE_TEMP_DIR}/sketches/${LIBRARY}}"
 
     mkdir -p "$CORE_CACHE_PATH"
     mkdir -p "$BUILD_PATH"
@@ -216,7 +215,7 @@ compile () {
 
     install -d "${OUTPUT_PATH}"
 
-    echo "Building ${OUTPUT_DIR}/${SKETCH} (${LIB_VERSION}) ..."
+    echo "Building ${SKETCH} (${LIB_VERSION}) ..."
 
     # This is defined in the (optional) user config.
     # shellcheck disable=SC2154
@@ -279,6 +278,8 @@ compile () {
     ln -sf "${OUTPUT_FILE_PREFIX}.hex" "${OUTPUT_PATH}/${SKETCH}-latest.hex"
     ln -sf "${OUTPUT_FILE_PREFIX}.elf" "${OUTPUT_PATH}/${SKETCH}-latest.elf"
 
+    echo "Your compiled sketch can be found in ${OUTPUT_PATH}"
+
     if [ "${ARDUINO_VERBOSE}" = "-verbose" ]; then
 	      echo "Build artifacts can be found in ${BUILD_PATH}";
     fi