[TYPO3-typo3org] Online rendering of manuals adds empty sections to the table of content

[Peter Klein]

I noticed a small problem with one of my extensions manual, when it's 
displayed online at typo3.org.
http://typo3.org/documentation/document-library/extension-manuals/pmkshadowbox/1.0.0/view/toc/0/

Notice the "Table of content" has an item "Extension Manuals" which appers 
several times. (This header is not in the manual .sxw of my extension)