All general elections for State and county officers shall commence and be holden every four years, on the first Tuesday after the first Monday in November, until altered by law; and the electors, in all cases except in cases of treason, felony and breach of the peace, shall be privileged from arrest during their attendance at elections and in going to and returning therefrom. . In all cases not otherwise provided for in this constitution, the legislature may determine the mode of filling all vacancies, in all offices, and in cases of emergency provisional appointments may be made by the governor, to continue until the vacancy is regularly filled; and the legislature shall provide suitable compensation for all officers, and shall define their respective powers.