commit #21848 for htdocs: Fix facebook like button

[Cristian Marchi]

I've noticed that the commit #21848[1] commit broke the validation of 
the gnucash website. I don't really know what it does but I remember 
I've used that code because it was adviced (browsing the internet) to do 
so for validation purpose. While working with the website I've always 
aimed to have it validated (XHTML+RDFa as of now) but I don't really 
know if it is of any use.

Regards
Cristian

[1] 
http://svn.gnucash.org/trac/changeset?reponame=&new=21848%40htdocs%2Ftrunk&old=21769%40htdocs%2Ftrunk