made level 10 a bit faster
made level 10 a bit faster

at the expense of a little bit of compression ratio.

Now speed is intermediate on calgary corpus :
25 - 12 - 8 - 3

unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso