License header

[Thilo Goetz <tw...@gmx.de>]

I have noticed that some of our source files have no license headers, 
some have the wrong one.  Please remember to add license headers to all 
files that we distribute.  This includes XML files etc., not just Java 
source code.  The only (standard) exceptions are generated files, such 
as javadoc html files, as well as files where we can't include a license 
header for format reasons.

Please find the correct header here: 
http://www.apache.org/legal/src-headers.html#headers

Thanks,
Thilo