When taking a screenshot using the keyboard shortcut
shift+command+3 it yields a screenshot with a filename of
Screen Shot 2014-11-23 at 3.25.36 PM.png. I would like to make a change so that the filename would be
scr-20141123-152536.png. This would be the same exact date and time but altered to what I have been using for the past 13 years on other systems - it just works better for me. Is it possible to make this a permanent change? And, if so, how would I make this change?
UPDATE: I don't want to install Macports or Homebrew, or other package management system or apps that require the user to disable system security in order to run.
My system: Mac mini, late 2012, OS X 10.10.1 (Yosemite)