non-working CMDB search bug fixed

The CMDB search dialog is not working correctly since OTRS4 (see also http://forums.otterhub.org/viewtopic.php?f=62&p=108942). This issue is not resolved with 4.0.2 and could be reproduced on a clean OTRS4 install.

When clicking CMDB > Search, the window pops up but stays empty except for the title. The class option dropdown is not rendered and the remaining parts of the dialog are hidden.

![cmdb_search_not_working](https://cloud.githubusercontent.com/assets/7870562/5392921/03677c80-812c-11e4-946f-e33b9978a78b.png)

Adding a newline after [% RenderBlockStart("SearchAJAX") %] seems to fix the problem.