Add tepl, amtk, and uchardet, new gedit dependencies

Hey @akitouni, I looked at the scan-for-dev-files.sh from freedesktop-sdk but it looks like it's intended to be used from inside a built runtime? I guess these elements don't need split rules anyway because they are core-deps rather than sdk? Or do you want devel split-rules for everything?

Either way, it would be helpful to have an easier want to sniff out devel files that need to be split. :)