fix XElement copy, added unit tests & vsproject

[brainbaking]

Hi there,

Thanks for your deep clone utility class! Turns out XElement is not that easily fooled, you have to use their own copy constructor, I fixed that. Also added some unit tests and created a VStudio project for it.

If you'd like, you can join this commit onto your master branch.

Thanks again,
-- Wouter.

[Burtsev-Alexey]

Interesting, gonna check out XElement source codes, but theoretically any .NET code could be copied by this code. Unless XElement uses unmanaged code, or deal with pointers.

[brainbaking]

XElement inherits from XContainer and contains an internal object "content" but everything seems to get copied over just fine. Linq expressions like .However, Elements() don't produce the wanted result. I peeked into the Linq source and they simply traverse the content object (as an XNode) so why shouldn't it work indeed?

[brainbaking]

any news on this? Thx!