Revert the commits that change OpArrayLength type and bumped the version number.

Now, version 5.* is all connected to making the uint type, which doesn't quite work.
Generator versions 4 and 6 do not do this.

SPIRV/SpvBuilder.cpp

@@ -1177,7 +1177,7 @@ Id Builder::createAccessChain(StorageClass storageClass, Id base, const std::vec
 
 Id Builder::createArrayLength(Id base, unsigned int member)
 {
-    spv::Id intType = makeUintType(32);
+    spv::Id intType = makeIntType(32);
     Instruction* length = new Instruction(getUniqueId(), intType, OpArrayLength);
     length->addIdOperand(base);
     length->addImmediateOperand(member);