Support DnD for problem markers and search matches

[sandy081]

In Problems/Search view, one can DnD a file resource into editor. This request is to support the same functionality for Problem Marker entries and Search match entries.

[sandy081]

To support range selection in URI, extended URI fragment selection syntax to support ranges. Eg:

file:///some/file.js#73,84-83,52
file:///some/file.js#L73,84-L83,52

[sandy081]

CC @roblourens - Search matches also support this behavior now.