Gradebook shows up nicely. Announcements still shows modules with no announcements.

Gradebook works. Only showing item name, marks, grade, and percentile for
now. Need to trim the announcements code a little more, because it still
shows the module codes when the module has no announcements. Should I show
all modules regardless of number of announcements? Anyway, logout button
on home page is tidied up also.

Signed-off-by: nicholaslum444 <nicholaslum444@hotmail.com>