Merge pull request #21 from chamilo/1.9.x

1.9.x
Merge pull request #22 from chamilo/1.9.x

1.9.x
Merge pull request #23 from chamilo/1.9.x

1.9.x
Merge pull request #24 from chamilo/1.9.x

1.9.x
Merge pull request #25 from chamilo/1.9.x

1.9.x
Adding Search box -refs #6883
Adding Search box -refs #6883
Indentation
Indentation
Merge pull request #189 from ycastillo/6883

Implement AJAX search box for assigning tracked users - refs #6883