Do not accept links in editor that only work due to acquisition

[Martijn Faassen]

When a user enters a relative link in an editor (kupu or forms based), links
that only work due to acquisition shouldn't be accepted.

This could be done by finding the object they would refer to thanks to
acquisition, and constructing a relative (or absolute) path to them instead,
storing *that* in the XML.

This allows us to stop worrying about this issue when rendering a document with
a public URL in it.

Some complexities involving ghosts and virtual hostings probably still exist though.

We also need a conversion script which fixes all acquisition based links that
may be in the XML.

[Martijn Faassen (faassen)]

Ideally we solve this for 1.1 and provide an upgrade script. I can see that due
to lack of time this needs to be moved to 1.2 though.

[Martijn Faassen (faassen)]

This is probably a fairly complicated thing to solve at this time, so moving
into future.

[Sylvain Viollon (thefunny)]

Those links are no longer accepted as you cannot input them. The proper way to add a link now is with the reference lookup, and this doesn't store a path. So there is no issue this path will only work because of the acquisition. This have been released in Silva 2.3.