Squashed commit of the following:

commit 6b231fa023c8b22bd701ba9f9b990fa60e7a567e
Author: Bevan Rudge <bevan@drupal.geek.nz>
Date:   Tue Oct 8 16:25:03 2013 +1300

    #365 Update the xpaths to look for exact matches instead of contains().

commit a0b6f925740ff368d0ef2e779adfb1d960866056
Author: Bevan Rudge <bevan@drupal.geek.nz>
Date:   Tue Oct 8 14:10:50 2013 +1300

    \#365 Adds ExactSelector (sub-class of NamedSelector) to allow exact matching instead of partial matching.