Define X-KDE-ConfigModule property instead of relying on KServiceTypeTrader

Relates to https://phabricator.kde.org/T12265

transfer-plugins/bittorrent/kget_bittorrentfactory.desktop

@@ -120,6 +120,7 @@ X-KDE-Library=kget_bittorrentfactory
 X-KDE-KGet-plugintype=TransferFactory
 X-KDE-KGet-rank=200
 X-KDE-KGet-framework-version=2
+X-KDE-ConfigModule=kget/kcms/kcm_kget_bittorrentfactory
 
 X-KDE-PluginInfo-Author=Lukas Appelhans
 X-KDE-PluginInfo-Email=l.appelhans@gmx.de

transfer-plugins/checksumsearch/kget_checksumsearchfactory.desktop

@@ -115,6 +115,7 @@ X-KDE-Library=kget_checksumsearchfactory
 X-KDE-KGet-plugintype=TransferFactory
 X-KDE-KGet-rank=30
 X-KDE-KGet-framework-version=2
+X-KDE-ConfigModule=kget/kcms/kcm_kget_checksumsearchfactory
 
 X-KDE-PluginInfo-Author=Matthias Fuchs
 X-KDE-PluginInfo-Email=mat69@gmx.net

transfer-plugins/metalink/kget_metalinkfactory.desktop

@@ -119,6 +119,7 @@ X-KDE-Library=kget_metalinkfactory
 X-KDE-KGet-plugintype=TransferFactory
 X-KDE-KGet-rank=110
 X-KDE-KGet-framework-version=2
+X-KDE-ConfigModule=kget/kcms/kcm_kget_metalinkfactory
 
 X-KDE-PluginInfo-Author=Manolo Valdes
 X-KDE-PluginInfo-Email=nolis71cu@gmail.com

transfer-plugins/mirrorsearch/kget_mirrorsearchfactory.desktop

@@ -119,6 +119,7 @@ X-KDE-Library=kget_mirrorsearchfactory
 X-KDE-KGet-plugintype=TransferFactory
 X-KDE-KGet-rank=40
 X-KDE-KGet-framework-version=2
+X-KDE-ConfigModule=kget/kcms/kcm_kget_mirrorsearchfactory
 
 X-KDE-PluginInfo-Author=Manolo Valdes
 X-KDE-PluginInfo-Email=nolis71cu@gmail.com

transfer-plugins/mmsthreads/kget_mmsfactory.desktop

@@ -126,6 +126,7 @@ X-KDE-Library=kget_mmsfactory
 X-KDE-KGet-plugintype=TransferFactory
 X-KDE-KGet-rank=80
 X-KDE-KGet-framework-version=2
+X-KDE-ConfigModule=kget/kcms/kcm_kget_mmsfactory
 
 X-KDE-PluginInfo-Author=Ernesto Rodriguez Ortiz
 X-KDE-PluginInfo-Email=eortiz@uci.cu