Limit max.print to be at most 10000

If .Rprofile has max.print set to a low value like 100 (common if the user routinely works with datasets that lock up the screen for minutes at a time even with 10000 rows), then just calling options(max.print = 10000) will silently override their wishes.
Merge pull request #179 from yn/master

Limit max.print to be at most 10000