Description of problem:
dnf installs group kde-desktop-environment fine, but fails when trying to mark it installed. this didn't occur with lxqt-desktop-environment or workstation-product-environment

Version-Release number of selected component (if applicable):


How reproducible:
Random

Steps to Reproduce:
1. install group 
2. try to mark it installed

Actual results:

root@mongo:~# dnf group mark install kde-desktop-environment
Last metadata expiration check performed 0:24:05 ago on Sat Jun  6 15:31:57 2015.
Traceback (most recent call last):
  File "/usr/bin/dnf", line 36, in <module>
    main.user_main(sys.argv[1:], exit_code=True)
  File "/usr/lib/python2.7/site-packages/dnf/cli/main.py", line 185, in user_main
    errcode = main(args)
  File "/usr/lib/python2.7/site-packages/dnf/cli/main.py", line 84, in main
    return _main(base, args)
  File "/usr/lib/python2.7/site-packages/dnf/cli/main.py", line 134, in _main
    cli.run()
  File "/usr/lib/python2.7/site-packages/dnf/cli/cli.py", line 1077, in run
    return self.command.run(self.base.extcmds)
  File "/usr/lib/python2.7/site-packages/dnf/cli/commands/group.py", line 379, in run
    return self._mark_install(extcmds)
  File "/usr/lib/python2.7/site-packages/dnf/cli/commands/group.py", line 236, in _mark_install
    res.environments, types)
  File "/usr/lib/python2.7/site-packages/dnf/comps.py", line 88, in install_or_skip
    logger.warning("%s, %s", str(e)[:-1], _("skipping."))
UnicodeEncodeError: 'ascii' codec can't encode character u'\xf6' in position 27: ordinal not in range(128)
root@mongo:~# 


Expected results:
marking group installed succeeding

Additional info:
- system language is Finnish (maybe related to unicode error? we have lots of ä & ö)
- everything was up to date prior installing group
- trying to rerun group install after failing to mark it installed produces the exact same errors
- cleaning dnf caches doesn't help