Vectors are not integer types, so the type system should not classify

them as such. Type::is(Signed|Unsigned|)IntegerType() now return false
for vector types, and new functions
has(Signed|Unsigned|)IntegerRepresentation() cover integer types and
vector-of-integer types. This fixes a bunch of latent bugs.

Patch from Anton Yartsev!

llvm-svn: 109229