Doc: Add Setting Up a Qbs Project to the TOC

This currently only affects the fixnavi script.

Change-Id: I08806d20fb52167961a4c763342623b39f66a177
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@digia.com>

doc/src/qtcreator.qdoc

@@ -286,6 +286,7 @@
             \li \l{Using Other Build Systems}
             \list
                 \li \l{Setting Up a CMake Project}
+                \li \l{Setting Up a Qbs Project}
                 \li \l{Setting Up an Autotools Project}
                 \li \l{Setting Up a Generic Project}
             \endlist