Improvements to the |cleanHtml soy directive:

1. Add support for specifying optional tags to also whitelist as safe when the caller wants to treat them as innocuous: <ol>, <ul>, <li>, and <span>.

2. Preserve the "dir" attribute for elements that make it through the whitelist.

These allow teams to avoid having to add santizedcontent ordainers for simple cases, such as HTML that is santized on a trusted backend but leaves spans with different directionality in the HTML to support different text directionality.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78294767

Conflicts:
	javadoc-complete/com/google/template/soy/shared/restricted/Sanitizers.html
	javadoc-complete/index-all.html
Remove the non-Closure version of Soyutils.

All the existing usages were pretty easy to fix, and I sent out a Rosie for
them all.  This fixes the final usages within Soy itself and removes all traces
of them.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=78612967