Context aware search results

Something I find ILSpy has been missing is a context aware search, the search results are largely irrelevant. By using a ObservableSortedList and a string edit distance algorithm we can get search results that better capture our intention.

I pulled in an existing ObservableSortedList (from the web) and the Levenstein distance (from simmetrics, I scrapped to double, string indexing and abstractions, it just makes it unnecessarily slow) as prof of concept. If any of these implementations are not OK, please take into consideration, adding a feature like this. I find it to be a much more direct approach to get at what you want.

This works by simply prioritizing the edit distance over the sort order, feel free to fiddle with the controls but I wanted to illustrate how I think search results could be further improved.

As you'l surly notice, this implementation has some quirks to it, I simplified to the problem to get the idea across initially, this code will run but it will not work with multi-term searches or search types not based on the `.Name` property.