Fixed a stringification bug in ViewManager.materialize
Fixed a stringification bug in ViewManager.materialize

A little bug with automatic type inference in ViewManager.  Specifically, Compiler.sqlForBackend now emits schema information.  That is, the return type is (SelectBody, Seq[(String,Type)]).  However, ViewManager was just using the return value untyped for materialization, and then calling toString on it, so Scala's typechecker didn't catch it.  Types have now been assigned.

UBOdin/mimir,UBOdin/mimir,UBOdin/mimir