Introduced `contact-send` filter. Ability to disable spamcheck via shortcode using `spamcheck="false"`. Added Ukrainian (uk_UA) language translation. Allow for additional attributes to be passed through to template files.

git-svn-id: https://plugins.svn.wordpress.org/contact/trunk@1004310 b8457f37-d9ea-0310-8a92-e5e31aec5664