update path, comment format, add java, firebase

install/99-screenfetch.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+
+if not_installed "screenfetch"; then
+    echo "Installing screenfetch..."
+    install screenfetch
+fi
+
+echo "screenfetch is installed"
+screenfetch --version
+screenfetch