CI: Add helper functions

Add a shell script that can produce colorfull output to help to identify
problems during CI runs.

Signed-off-by: Michal Hrusecky <michal.hrusecky@turris.com>

.github/workflows/ci_helpers.sh

@@ -0,0 +1,26 @@
+#!/bin/sh
+
+color_out() {
+	printf "\e[0;$1m$PKG_NAME: %s\e[0;0m\n" "$2"
+}
+
+success() {
+	color_out 32 "$1"
+}
+
+info() {
+	color_out 36 "$1"
+}
+
+err() {
+	color_out 31 "$1"
+}
+
+warn() {
+	color_out 33 "$1"
+}
+
+err_die() {
+	err "$1"
+	exit 1
+}