Breadcrumb Rich Snippets Microdata

Using Google rich snippets tools
(http://www.google.com/webmasters/tools/richsnippets) and I found out
that the microdata format is not completely correct.

I think the changes I made fixed that issue.
Update breadcrumb.php

Added a newline
Update breadcrumb.php

Readability improvement
Update the concatenation style

Change the concatenation style as proposed by @zcwilt, @drbyte and @texdc.
Merge pull request #134 from IronLady/upstream

Breadcrumb Rich Snippets Microdata