Add page breaking and block rules to dl elements. This appears to fix #2.

The `dl` elements have been given an explicit `display:block` and page
break avoid rule. In initial testing, this fixes the wkhtmltopdf bug of
splitting lines in a multi-page document.

See http://stackoverflow.com/questions/8786755 for links and discussion.

.gitignore

@@ -1,3 +1,5 @@
 resume/_*.md
 output/*.html
 output/*.pdf
+
+resume/sample_long.md