Exercises page should be more like Edit Worksheets

[Matt Giuca]

Compare the Exercises page (http://ivle.localhost/+exercises) to the Edit Worksheets page (http://ivle.localhost/subjects/ivle-102/2009/2/+worksheets/+edit). The Edit Worksheets page is much better, so make the Exercises page more like it:

- Call it "Edit Exercises", not just "Exercises", with a heading "Editing exercises",
- Rename "Create an exercise" to "Create new exercise", for consistency,
- *Do* show both the URL name and display name (unlike worksheets, because it's more common to refer to an exercise by urlname, and also harder to find),
- Replace the horrible ul with wacky divs with a table,
- Add an edit button next to each exercise,
- Sort the page if it isn't already.

[Matt Giuca (mgiuca)]

All requests done, fixed in trunk r1506.

[Matt Giuca (mgiuca)]

Forgot to mark as committed.