Grid object should expose line properties
legend renderer need to check do_stroke and do_fill
Squashed 'subtree/bokehjs/' changes from c9a10b3..cd96f66

cd96f66 guides should round to whole pixel coordinates to appear sharper

git-subtree-dir: subtree/bokehjs
git-subtree-split: cd96f66931cba49f6eaa04ddc4a3a973a226e5b7
Merge commit '5fcb35846b5bfca65ab3e3b273ee6fec1e855441'