Hover Inconsistency for Absolute Paths

[montymxb]

Full details from #424 , relatively small issue otherwise:

There's a small existing issue in the hover logic on windows based on the hover logic computation when a lib (from a process group) is absolute but not a windows drive letter. This leads to a mismatch between the from/to uris when the lib entry is something like /A/... instead of C:/A/.... The path still resolves in the context of the current drive letter, but on hover displays as ./A/....