Debug window - Use one active buffer and one pause buffer per service

Debug window - Use one active buffer and one pause buffer per service

-Remove cache and store.
-Add one proxy and and related data per service in service_chooser
-Add one list store per service in service_chooser to save logs
-Make the service chooser switch the correct list store to display
-Free proxy_data before disposing service_store
-Fix "Clear" operation
-Fix searching
-Setting the correct store_filter on switching services
-Adding COL_PAUSE_BUFFER to service_store
-Deploy one pause-buffer per proxy

https://bugzilla.gnome.org/show_bug.cgi?id=592994