Hi,
This is an extremely simple, but in my opinion quite useful Add-on that allows you to “enable” Add-ons according to *.blend files instead of “User Preferences”.
Wiki:
https://studio.allblue.pl/wiki/wikis/blender/addons-tools/
Download:
https://studio.allblue.pl/wiki/wikis/blender/addons-tools/releases
Tutorial (video):
Hope it will come in handy for some of you.
Cheers