Add hyperlinks to Makefile output

Add hyperlinks in the Makefile output so you can easily ctrl-click the link to open the HTML/PDFs.

Author: Timmmm

Makefile

@@ -139,16 +139,19 @@ $(BUILD_DIR)/%.pdf: $(SRC_DIR)/%.adoc $(ALL_SRCS)
 	$(WORKDIR_SETUP)
 	$(DOCKER_CMD) $(DOCKER_QUOTE) $(ASCIIDOCTOR_PDF) $(OPTIONS) $(REQUIRES) $< $(DOCKER_QUOTE)
 	$(WORKDIR_TEARDOWN)
+	@echo -e '\n  Built \e]8;;file://$(abspath $@)\e\\$@\e]8;;\e\\\n'
 
 $(BUILD_DIR)/%.html: $(SRC_DIR)/%.adoc $(ALL_SRCS)
 	$(WORKDIR_SETUP)
 	$(DOCKER_CMD) $(DOCKER_QUOTE) $(ASCIIDOCTOR_HTML) $(OPTIONS) $(REQUIRES) $< $(DOCKER_QUOTE)
 	$(WORKDIR_TEARDOWN)
+	@echo -e '\n  Built \e]8;;file://$(abspath $@)\e\\$@\e]8;;\e\\\n'
 
 $(BUILD_DIR)/%.epub: $(SRC_DIR)/%.adoc $(ALL_SRCS)
 	$(WORKDIR_SETUP)
 	$(DOCKER_CMD) $(DOCKER_QUOTE) $(ASCIIDOCTOR_EPUB) $(OPTIONS) $(REQUIRES) $< $(DOCKER_QUOTE)
 	$(WORKDIR_TEARDOWN)
+	@echo -e '\n  Built \e]8;;file://$(abspath $@)\e\\$@\e]8;;\e\\\n'
 
 build: submodule-check
 	@echo "Checking if Docker is available..."