Document the fact that "breakpoint modify" with no breakpoint acts on the 
last created breakpoint.

llvm-svn: 120850
diff --git a/lldb/source/Commands/CommandObjectBreakpoint.cpp b/lldb/source/Commands/CommandObjectBreakpoint.cpp
index 5dc5c0a..1217164 100644
--- a/lldb/source/Commands/CommandObjectBreakpoint.cpp
+++ b/lldb/source/Commands/CommandObjectBreakpoint.cpp
@@ -1486,7 +1486,8 @@
 CommandObjectBreakpointModify::CommandObjectBreakpointModify (CommandInterpreter &interpreter) :
     CommandObject (interpreter,
                    "breakpoint modify", 
-                   "Modify the options on a breakpoint or set of breakpoints in the executable.", 
+                   "Modify the options on a breakpoint or set of breakpoints in the executable.  "
+                   "If no breakpoint is specified, acts on the last created breakpoint.", 
                    NULL)
 {
     CommandArgumentEntry arg;