feat(hott/homotopy/EM): redefine Eilenberg-Maclane spaces and prove their uniqueness
feat(hott/homotopy/EM): redefine Eilenberg-Maclane spaces and prove their uniqueness

fpvandoorn/lean2,fpvandoorn/lean2,fpvandoorn/lean2,fpvandoorn/lean2,fpvandoorn/lean2