[Building Sakai] lessons support for antisamy

[Charles Hedrick]

I've just added support of rantisamy. I need to get it in immediately, or 2.9.2 may cause unexpected results.

When dealing with user HTML, currently for instructors I do no filtering. 
WIth antinomy I believe I should use LOW, although many sites will probably need to set it to NONE.

The problem is that I can't tell what default to use. I can tell whether we have antisamy code. I currently say that if we have the code I default to LOW. The problem is that we may have the code but it may be disabled. There is no API call to tell whether it's disabled. 

What would you say to making useLegacyCleaner public? Otherwise the only thing I can think to do is to call it via introspection. I'm willing to do that, but I consider it ugly to call non-public methods in the kernel ,although I have the mechanics to do that set up.