Improved statusbar output for the debugger mode

* We now consistently avoid punctuation when possible
* Renamed usage of "Inferior" and "Program" to "Application" for
  increased readability
* Fixed inconsistent spacing in front of statusbar label

Reviewed-by:hjk

src/plugins/debugger/debuggerplugin.cpp

@@ -1006,6 +1006,7 @@ bool DebuggerPlugin::initialize(const QStringList &arguments, QString *errorMess
         m_manager->threadsWindow(), SIGNAL(threadSelected(int)));
 
     hbox->addWidget(threadBox);
+    hbox->addSpacerItem(new QSpacerItem(4, 0));
     hbox->addWidget(m_manager->statusLabel(), 10);