[Packaging] Remove "NFS support" part from the package description

[Ｖ字龍(Vdragon)]

[Upstream already remove NFS support since 2011/2/19](https://projects.kde.org/projects/kde/kdenetwork/kdenetwork-filesharing/repository/revisions/cb4fc5f59), users had been confused by the incorrect package description[1], please update the package description accordingly.

[1] http://www.ubuntu-tw.org/modules/newbb/viewtopic.php?viewmode=flat&type=&topic_id=103374&forum=22

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: kdenetwork-filesharing 4:4.13.0-0ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-71.114-generic 3.13.11-ckt29
Uname: Linux 3.13.0-71-generic i686
NonfreeKernelModules: nvidia
ApportVersion: 2.14.1-0ubuntu3.19
Architecture: i386
CurrentDesktop: Unity
Date: Wed Dec 16 14:34:21 2015
InstallationDate: Installed on 2015-10-02 (74 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release i386 (20140417)
SourcePackage: kdenetwork-filesharing
UpgradeStatus: No upgrade log present (probably fresh install)