chore: re-organize files inside assets/ (second try) (#1952)

Change-Type: patch
See: https://github.com/resin-io/etcher/pull/1941
Signed-off-by: Juan Cruz Viotti <jv@jviotti.com>

Makefile

@@ -284,16 +284,16 @@ $(BUILD_DIRECTORY)/$(APPLICATION_NAME)-cli-$(APPLICATION_VERSION)-$(PLATFORM)-$(
 # GUI
 # ---------------------------------------------------------------------
 
-assets/dmg-installer.tiff: assets/dmg-installer.png assets/dmg-installer@2x.png
+assets/dmg/background.tiff: assets/dmg/background.png assets/dmg/background@2x.png
 	tiffutil -cathidpicheck $^ -out $@
 
-$(BUILD_DIRECTORY)/$(APPLICATION_NAME)-$(APPLICATION_VERSION).dmg: assets/dmg-installer.tiff \
+$(BUILD_DIRECTORY)/$(APPLICATION_NAME)-$(APPLICATION_VERSION).dmg: assets/dmg/background.tiff \
 	| $(BUILD_DIRECTORY)
 	TARGET_ARCH=$(TARGET_ARCH) build --mac dmg $(ELECTRON_BUILDER_OPTIONS) \
 		--extraMetadata.version=$(APPLICATION_VERSION) \
 		--extraMetadata.packageType=dmg
 
-$(BUILD_DIRECTORY)/$(APPLICATION_NAME)-$(APPLICATION_VERSION)-mac.zip: assets/dmg-installer.tiff \
+$(BUILD_DIRECTORY)/$(APPLICATION_NAME)-$(APPLICATION_VERSION)-mac.zip: assets/dmg/background.tiff \
 	| $(BUILD_DIRECTORY)
 	TARGET_ARCH=$(TARGET_ARCH) build --mac zip $(ELECTRON_BUILDER_OPTIONS) \
 		--extraMetadata.version=$(APPLICATION_VERSION) \

electron-builder.yml

@@ -13,7 +13,7 @@ mac:
   icon: assets/icon.icns
   category: public.app-category.developer-tools
 dmg:
-  background: assets/dmg-installer.tiff
+  background: assets/dmg/background.tiff
   icon: assets/icon.icns
   iconSize: 110
   contents:
@@ -44,7 +44,7 @@ linux:
   packageCategory: utils
   executableName: etcher-electron
   synopsis: Etcher is a powerful OS image flasher built with web technologies to ensure flashing an SDCard or USB drive is a pleasant and safe experience. It protects you from accidentally writing to your hard-drives, ensures every byte of data was written correctly and much more.
-  icon: assets
+  icon: assets/iconset
 deb:
   priority: optional
   depends: