Courses missing navigation arrows

[syz16]

Trigonometry and Modular Arithmetic don't have navigation arrows at the bottom of the page.

[saumyasinghal747]

You can do it for trig, but don't waste time on MA. I've deprecated it.
EDIT: Canceling Deprecation.

[saumyasinghal747]

BTW** We'll soon be replacing MA with Exp. We can make an archive page for old, deprecated courses like MA.
EDIT: canceling deprecation. Please add arrows to MA!