qttest: Disable default load of plugin til parsing times are improved

Change-Id: Ib29cae27ec9666d31df571a9c87dfc2a24644f09
Reviewed-on: http://codereview.qt.nokia.com/4020


Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Bill King <bill.king@nokia.com>

src/plugins/qttest/QtTest.pluginspec.in

-<plugin name=\"QtTest\" version=\"$$QTCREATOR_VERSION\" compatVersion=\"$$QTCREATOR_VERSION\">
+<plugin name=\"QtTest\" version=\"$$QTCREATOR_VERSION\" compatVersion=\"$$QTCREATOR_VERSION\" experimental=\"true\">
     <vendor>Nokia Corporation</vendor>
     <copyright>(C) 2011 Nokia Corporation</copyright>
     <license>