Remove UNIQUE constraint on Guid columns since in makes no sense but degrades write performance by 6x and in certain case read performance ("IN" clause in "WHERE" with a lot of values). Single value lookup is as fast with "LIMIT 1;" as with UNIQUE constraint.

The only "concern" with Guid is it takes 16*2 = 32 bytes per each row (16 as data + 16 in index), but memory is cheaper than everything else in equation (Note to myself: repeat in 1000 in handwriting to stop counting these bytes when a typical row is 1kb-100kb!)

TODO: Put binary of custom version of v3 SS.ORMLite.MySQL here with 'bynary(16)' instead of 'char(32)' and byte flip trick to make hex(Guid) in MySQL look the same as Guid.ToString("N") in C#. Anyway it is used for tests and benchmarks.