Fix gzinflate for strings larger than 128M

Fix gzinflate for strings larger than 128M

gzinflate tries to do some kind of exponential growth that
hits the max string limit immediately when you try to deflate a string
larger than 128 megs.  The logic is a little convoluted with a few
ways to bail, but rather than try to really fix it I just made it
behave close to the same on small strings, but use a smaller starting
factor on long ones and be willing to try to deflate it into a
max-sized string.