Typer: reintroduce consistency checking
Typer: reintroduce consistency checking

ocaml/merlin,dra27/merlin,rgrinberg/merlin,ocaml/merlin,fxfactorial/merlin,ocaml/merlin,chriskonstad/merlin,dra27/merlin,the-lambda-church/merlin,chambart/merlin,chambart/merlin,rgrinberg/merlin,rgrinberg/merlin,chriskonstad/merlin,dra27/merlin,dra27/merlin,chambart/merlin,chambart/merlin,rgrinberg/merlin,fxfactorial/merlin,fxfactorial/merlin,ocaml/merlin,the-lambda-church/merlin,fxfactorial/merlin,the-lambda-church/merlin