feat(CMakeLists.txt): install *.md in standard/hott libraries 
feat(CMakeLists.txt): install *.md in standard/hott libraries 

close #823
soonhokong/lean,soonhokong/lean-osx,fpvandoorn/lean,javra/lean,rlewis1988/lean,fgdorais/lean,soonhokong/lean-windows,leanprover-community/lean,UlrikBuchholtz/lean,fpvandoorn/lean,rlewis1988/lean,digama0/lean,leodemoura/lean,avigad/lean,soonhokong/lean-osx,UlrikBuchholtz/lean,soonhokong/lean,soonhokong/lean-osx,levnach/lean,fgdorais/lean,avigad/lean,leodemoura/lean,digama0/lean,Kha/lean,dselsam/lean,leanprover/lean,rlewis1988/lean,soonhokong/lean,johoelzl/lean,fgdorais/lean,leanprover-community/lean,levnach/lean,UlrikBuchholtz/lean,fpvandoorn/lean,javra/lean,levnach/lean,soonhokong/lean-windows,leanprover-community/lean,soonhokong/lean-osx,soonhokong/lean,avigad/lean,Kha/lean,dselsam/lean,soonhokong/lean,avigad/lean,levnach/lean,soonhokong/lean-osx,fpvandoorn/lean2,leanprover-community/lean,dselsam/lean,UlrikBuchholtz/lean,soonhokong/lean-windows,avigad/lean,fpvandoorn/lean,digama0/lean,leanprover-community/lean,Kha/lean,leodemoura/lean,leodemoura/lean,fpvandoorn/lean,Kha/lean,leodemoura/lean,fpvandoorn/lean,fpvandoorn/lean2,digama0/lean,johoelzl/lean,levnach/lean,javra/lean,leanprover/lean,johoelzl/lean,soonhokong/lean-windows,soonhokong/lean-windows,rlewis1988/lean,javra/lean,avigad/lean,fgdorais/lean,fgdorais/lean,fgdorais/lean,fpvandoorn/lean2,Kha/lean,javra/lean,fpvandoorn/lean2,fpvandoorn/lean2,johoelzl/lean,digama0/lean,leanprover/lean,leodemoura/lean,rlewis1988/lean,rlewis1988/lean,leanprover/lean,leanprover-community/lean,dselsam/lean,digama0/lean,UlrikBuchholtz/lean,leanprover/lean,johoelzl/lean,dselsam/lean,dselsam/lean,leanprover/lean,johoelzl/lean,Kha/lean