name change proposal

In order to clarify some of the terms we use and allow use to make
better use of some already used terms, I am proposing the following name
changes. Let me know what you guys think.

terms:
modules (userbrowser.php)  -> pages
objects (course/event/action/etc objects)   -> modules
packages (course packages) -> sections

packages will then be used to refer to trellis course packages: a self
contained course within a zip file

tables:
courses          -> courses
courses_detail   -> courses_detail
packages         -> course_sections
objects          -> course_modules
objects_content  -> course_modules_data