Revert "Handle a '+' in organisation slugs"
Revert "Handle a '+' in organisation slugs"

This problem goes deeper than just a single slug.

This reverts commit 42d0edb5fcd71634dccf030cf3daa54e606de0f8.

ken-muturi/pombola,hzj123/56th,ken-muturi/pombola,geoffkilpin/pombola,geoffkilpin/pombola,geoffkilpin/pombola,mysociety/pombola,geoffkilpin/pombola,hzj123/56th,hzj123/56th,mysociety/pombola,ken-muturi/pombola,patricmutwiri/pombola,hzj123/56th,geoffkilpin/pombola,patricmutwiri/pombola,hzj123/56th,ken-muturi/pombola,mysociety/pombola,hzj123/56th,mysociety/pombola,ken-muturi/pombola,geoffkilpin/pombola,patricmutwiri/pombola,patricmutwiri/pombola,mysociety/pombola,ken-muturi/pombola,patricmutwiri/pombola,mysociety/pombola,patricmutwiri/pombola