How do I remap the 'take screenshot' in Starcraft 2 when playing on keyboard without F13/PrintScreen?

On a Mac, you can take a screenshot in two different ways.

1. If you want to use Starcraft's in game screenshot functionality, remap the key with Iber's answer, then find the screenshot in ~/Library/Application Support/Blizzard/StarCraft II/Accounts/(SC2 account ID)/(some other folder)/Screenshots/. I don't know what the some other folder's name signifies, as I sourced that information from this blog post and he didn't know either.

2. You can also use OS X built in screen capture: ⌘ Command+Shift+3 to save it as a png on your desktop. However before you must turn on Mac OS keyboard shortcuts in game options.

In game you must go to Options > Shortcuts (H) > Global > IU > "Make a screenshot" and then change F13 to the key of your choice.