[Building Sakai] Lesson Builder name change to Lessons

[Charles Hedrick]

Based on a suggestion from csev, I've changed the user-visible name of Lesson Builder to Lessons for trunk/1.4. Earlier versions remain unchanged. You can easily adjust this in tool/src/webapp/tools/sakai.lessonbuildertool.xml, although a few strings also refer to Lessons. You can make this change even if you don't build from source, once the war file has deployed.

Lessons is more consistent with the rest of Sakai, where we have names like Assignments, Tests and Quizes, and Forums.