CLC-2973 Organize instructor's My Academics by semester

https://jira.ets.berkeley.edu/jira/browse/CLC-2973

Designs are linked from the JIRA.

Added term_cd and term_yr to the academics feed to enable client-side sorted-merging of semesters. Not a bad idea to have them available anyway for consistency with My Classes.

Also implemented the existing designs for alternating color of the class rows in the semesters page. Since there is no spacing or border between courses, it's really too hard to follow long lists of classes otherwise.