Revert "Deny non-absolut import pathes"
Revert "Deny non-absolut import pathes"

This reverts commit b90abfb86814142b1483d9e540298607cf6894de.

Because `libimagcontact` is not based on `libimagentryref` anymore (as
of 2b10ab0b3627ea73cf4101112c035a81e2f1bd37), and thus does not put
pathes into the header, we can allow non-absolute pathes here.

matthiasbeyer/imag,matthiasbeyer/imag