change rfilter keyboard shorcut to ctrl+l because ctrl+i was already used.

data/gui/roster_window.ui

@@ -222,10 +222,10 @@
                       <object class="GtkCheckMenuItem" id="show_rfilter_menuitem">
                         <property name="visible">True</property>
                         <property name="events">GDK_POINTER_MOTION_MASK | GDK_POINTER_MOTION_HINT_MASK | GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK</property>
-                        <property name="label" translatable="yes">Show Roster F_ilter</property>
+                        <property name="label" translatable="yes">Show Roster Fi_lter</property>
                         <property name="use_underline">True</property>
                         <property name="active">False</property>
-                        <accelerator key="I" signal="activate" modifiers="GDK_CONTROL_MASK"/>
+                        <accelerator key="L" signal="activate" modifiers="GDK_CONTROL_MASK"/>
                         <signal name="toggled" handler="on_show_rfilter_menuitem_toggled"/>
                       </object>
                     </child>