D23736: Add a Term::Type::files() to filter excluding directories

[Méven Car]

meven added a dependent revision: D23742: Add two special cases url 
recentlyused:/files and recentlyused:/folders.

REPOSITORY
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REVISION DETAIL
  https://phabricator.kde.org/D23736

To: meven, ivan
Cc: kde-frameworks-devel, LeGast00n, GB_2, michaelh, ngraham, bruns