Doc: setting breakpoints before attaching to a running process

Task-number: QTCREATORBUG-3170

Reviewed-by: hjk

doc/qtcreator.qdoc

@@ -7201,8 +7201,6 @@
     \gui {Debug > Start Debugging > Start and Debug External Application...}
     and specify an executable.
 
-
-
     \section2 Launching in Terminal Mode
 
     To launch the debugger in the terminal mode, select \gui {Projects > Run Settings}
@@ -7215,6 +7213,10 @@
     \gui {Debug > Start Debugging >  Attach to Running External Application...},
     and then select a process by its name or process ID to attach to.
 
+    You can load the source project in advance and set breakpoints in it before
+    attaching to an already running process. For more information, see
+    \l{Setting Breakpoints}.
+
     \section2 Launching in Remote Mode
 
     The remote mode allows you to debug processes that run on remote machines.