MDL-37009 added class coursecat_renderable, added render(), altered course/index.php and course/category.php
rendering courses view page, unfinished
course listings are moved from front page to renderer as is
frontpage courses lists: replaced different functions with rendering coursecat_renderable
added enrolled users
big renaming
MDL-38304 moved editing functionality from course/search.php to course/manage.php
searching courses moved to renderer
added constants to displaycourses
correct rendering of list of tagged courses
MDL-37009 split html rendering into several functions, load content only if neede