updating license headers

Hi all,

Xindice is still using older version of license headers, the correct version can 
be found here [1]. I'll try to update headers sometime this week (end), which 
means I'll be touching lots of files.

If any of you folks (Todd? :) have local uncommitted changes, and such updates 
will disrupt your work, let me know :)

Vadim

[1] http://www.apache.org/legal/src-headers.html