Fix officer year level eligibility requirements

Under the previous constitution, members who would have the required
year level at the start of the required term were allowed to run for
officer positions. Omitting this was an oversight by the Constitution
Task Force in 2013.

Without this change, only students who are 4th years during the spring
semester would be eligible for President in the next year, and only 3rd
years would be eligible for Vice-President. This unnecessarily restricts
the highest leadership roles, preventing students who may not have taken
extra classes or arrived at RIT without extra transfer or AP credits
from being eligible for these positions until later in their careers.
Merge pull request #1 from rit-sse/election-eligibility

Fix officer year level eligibility requirements