fix a bug belongs to bloomfilter's command bfInsert

[631086083]

fix a bug of bfInsert command
items = [1, 2, 3, 5, 6, 4]
arrs = r.bfInsert('bfin1', items, 100, 1e-4, None, 2, None)
when we use this code it returns the array [1,1,1,1,1,1,1,0] ；because when it run，it runs the command is “BF.INSERT bfin1 CAPPCITY 100 ERROR 0.0001 ITEMS 1 2 3 4 5 6 EXPANSION 2” the last two elementaries are keys which are inserted into bloomfilter and not work for expansion 。 the correct work command is “ BF.INSERT bfin1 CAPPCITY 100 ERROR 0.0001 EXPANSION 2 ITEMS 1 2 3 4 5 6” ，in that case ，the items must be at the end of params。