Add unit tests for class QtOutputFormatterPrivate

    QtOutputFormatterPrivate(Project *proj)
        : qmlError(QLatin1String("(" QML_URL_REGEXP    // url
                                  ":\\d+"           // colon, line
                                  "(?::\\d+)?)"     // colon, column (optional)
                                  "[: \t]"))        // colon, space or tab
        , qtError(QLatin1String("Object::.*in (.*:\\d+)"))
        , qtAssert(QLatin1String("ASSERT: .* in file (.+, line \\d+)"))
        , qtAssertX(QLatin1String("ASSERT failure in .*: \".*\", file (.+, line \\d+)"))
        , qtTestFail(QLatin1String("^   Loc: \\[(.*)\\]"))
        , project(proj)
    {
    }