Explicit support for exotic paths on Windows

[ForNeVeR]

There are a plethora of various interesting types on Windows, including but not limited to:

• local device paths (\\.\…)
• root local device paths (\\?\…)

Read the comprehensive guide on the paths to learn more.

TruePath should at least support parsing and manipulating these. We should also decide what to do about path canonicalization: should we consider new AbsolutePath("C:\Foo") to be equal to new AbsolutePath("\\?\C:\Foo")? Should we trim the \\?\ part on parsing, and automatically add it back on path quoting if requested? These are for now open questions.

I am looking for a discussion on how these are used in reality, so that we can decide on what to do with them properly.