Provide a way to check if FSharpSymbolUse is resolved from id

When getting symbol uses via `GetAllUsesOfAllSymbolsInFile()` there're plenty of uses that were added implicitly or were resolved from syntax construction other than name use.
Examples:
* definition of optional parameter adds uses of OptionalParameterAttribute and its namespaces
* use of indexer property with `.[ ... ]`

May `ItemOccurence` type be extended with these cases?

```fsharp
module ClassLibrary32

type T() =
member x.Opt(?p: int) = ()
```