Refactor IO::All to use a hash based object

[ingydotnet]

Currently we use a file handle (glob ref). This issue should be resolved with as little other change as possible. We will likely lose the capability to use an IO::All::File object as a file handle, but that's probably OK.

[hginzel]

Why is it necessary? To loose the capability that IO::All::File is not a file handle is probably not OK. It would not be possible to use it in print, say and other functions.

[ingydotnet]

It's not necessary, but we thought it might make the code easier to maintain. My attempts to do this so far have been problematic, so I think it is possible that we will leave the object model asis.

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