Replace array_interleave() by phutil_implode_html()
Summary:
I like this abstraction better.
Result of phutil_implode_html() may be also used as a param of hsprintf().
Test Plan: None.
Reviewers: epriestley
Reviewed By: epriestley
CC: aran, Korvin
Differential Revision: https://secure.phabricator.com/D4904