bump version for CRAN release knitr v1.6

version 1.5 for CRAN, and start praying...

Bears!!

Greg @gfinak said this would be my last GIT commit message if I push to Github in Alaska, since I'll be there for vacation for the next week. Let's see if he is right. I hope not, of course.

Anyway, this is knitr v1.4, and I start to pray CRAN masters won't bite me. Well, it is way better for them to bite me rather than bears biting me in Alaska.

version 1.3 for CRAN

Revert "save a few seconds by not running `apt-get update` every time"

This reverts commit 44eb0db.

ready to release v1.1

version 1.0 is ready for CRAN

make news

bump version; ready to release

v0.7 should be ready now