column pinning prototype.
simplified pinning logic
making z-index 5 and standard on selection cells.
binding z-index to pinned state in template
getting pinning working with aggregates.
linking aggCol pinning with Selection checkbox pinning

also not running a digest when adding an agg column.
adding pushpin icons
updating build to 1.9.0
Merge pull request #166 from angular-ui/pinning

adding column pinning v 1.9
setting pinning to be false by default
updating workbench
fixing pinning jquery element selections.
commas suck
fixing comma problem.
no longer deep copy references

also using regular object equality to test for changes to data.