Silence the makefile recipes

Makefile is made up of recipes. Running a recipe in make, prints the recipe and also the output of every command in the recipe. Recipe can be implemented by re-directing the output to /dev/null device. But this approach has a problem. Sometimes, I wanted to read the output of the command and not be re-directed to /dev/null, especially during troubleshooting. In this situation, there is no other way but to change implementation of recipe to remove the redirection. Makefile has a switch -s to sile