This rule applies whenever an if statement is followed by one or more elsif statements; the final elsif
should be followed by an else statement.
The requirement for a final else statement is defensive programming.
The else statement should either take appropriate action or contain a suitable comment as to why no action is taken. This is
consistent with the requirement to have a final else clause in a case statement.
if x == 0 doSomething elsif x == 1 doSomethingElse end
if x == 0 doSomething elsif x == 1 doSomethingElse else raise 'An error has occured' end