public function testClear()
 {
     $this->assertEquals('lorem ipsum', StringUtils::clear('   lorem <i>ipsum</i>   '));
     $this->assertEquals('lorem ipsum dolor sit amet', StringUtils::clear('   lorem
         ipsum
 dolor <i>sit</i>,     (amet)'));
     $this->assertEquals('lorem ipsum dolor sit amet adipiscing elit', StringUtils::clear('  lorem `ipsum~ dolor !!! @sit #$ % ^ * (am/et) - _adipiscing+ = [ { } ] | \\ : ; " \' >< elit.???'));
     $this->assertEquals('lorem, ipsum/dolor sit amet', StringUtils::clear('lorem, ipsum/dolor sit amet    ', false));
 }