add travis log sections that can be folded
no longer silence R CMD check, since we have travis log sections now, and the output will not be too cluttered
write a message for the package to be installed
20 jobs is not enough; 2 were timeout
yihui updated branch pkg/knitr Mon Oct  6 01:37:39 CDT 2014
yihui updated branch pkg/knitr Mon Oct  6 13:00:30 CDT 2014