Transfer the NixOS patches for kpackage as of 2018-02-17:
- Allow external paths.
- Make QDirIterator follow symlinks.
Decided to use a patch for one of the "allow external paths" changes since
'substitute*' seems not to be robust enough.
* gnu/packages/patches/kpackage-allow-external-paths.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/kde-frameworks.scm(kpackage)[source]: Use it. <patch>: New
phase.