fix link to Z3 in README.md
fix link to Z3 in README.md
abakst/liquidhaskell,abakst/liquidhaskell,mightymoose/liquidhaskell,abakst/liquidhaskell,abakst/liquidhaskell,spinda/liquidhaskell,spinda/liquidhaskell,mightymoose/liquidhaskell,mightymoose/liquidhaskell,spinda/liquidhaskell,spinda/liquidhaskell,abakst/liquidhaskell,abakst/liquidhaskell,mightymoose/liquidhaskell,mightymoose/liquidhaskell,mightymoose/liquidhaskell,spinda/liquidhaskell,spinda/liquidhaskell