Readd ends_with from strings.ml.

Conflicts:
	bench/ce-bench
	bench/ce/algebraic_type_Z3,4.5.0.oracle
	bench/ce/array_records_Z3,4.5.0.oracle
	bench/ce/array_records_Z3,4.6.0.oracle
	bench/ce/arrays_Z3,4.5.0.oracle
	bench/ce/arrays_Z3,4.6.0.oracle
	bench/ce/floats_CVC4,1.5.oracle
	bench/ce/floats_Z3,4.5.0.oracle
	bench/ce/floats_Z3,4.6.0.oracle
	bench/ce/int32_Z3,4.5.0.oracle
	bench/ce/int32_Z3,4.6.0.oracle
	bench/ce/int_Z3,4.5.0.oracle
	bench/ce/int_overflow_Z3,4.5.0.oracle
	bench/ce/jlamp0_CVC4,1.5.oracle
	bench/ce/jlamp0_Z3,4.5.0.oracle
	bench/ce/jlamp0_Z3,4.6.0.oracle
	bench/ce/jlamp_array_CVC4,1.5.oracle
	bench/ce/jlamp_array_Z3,4.5.0.oracle
	bench/ce/jlamp_array_Z3,4.6.0.oracle
	bench/ce/jlamp_projections_Z3,4.5.0.oracle
	bench/ce/jlamp_projections_Z3,4.6.0.oracle
	bench/ce/map_CVC4,1.5.oracle
	bench/ce/map_Z3,4.5.0.oracle
	bench/ce/real_Z3,4.5.0.oracle
	bench/ce/real_Z3,4.6.0.oracle
	bench/ce/record_map_CVC4,1.5.oracle
	bench/ce/record_map_Z3,4.5.0.oracle
	bench/ce/record_map_Z3,4.6.0.oracle
	bench/ce/records_CVC4,1.5.oracle
	bench/ce/records_Z3,4.5.0.oracle
	bench/ce/ref_Z3,4.5.0.oracle
	bench/ce/ref_Z3,4.6.0.oracle
	bench/ce/simple_array_Z3,4.5.0.oracle
	src/printer/smtv2.ml