Out of 5 occurrences of `askLoadedTyped` and 4 occurrences of `loadedType` (non-definitional), I have manually set the `keepLoaded` parameter to the non-default `true` in two of them. That is because, of course, because it is necessary and tested to be so. 

In the particular case of occurrences, scala-refactoring depends on a global "load-all-before-index" and "remove-all-after" semantics (see [this comment](https://www.assembla.com/spaces/scala-ide/tickets/1001388-%60loadedtype%60-keeps-files-loaded-in-the-pc?comment=208788443#comment:208788443) by  Mirko).

I currently do not know how to refactor scala-refactoring quickly to load files parcimoniously throughout the index building process, and therefore would have difficulty removing that boolean very quickly. But I can switch to focusing on this if you consider it a blocker for this PR.