made a todo to update the scroll_to_cell function argument list for version 1.0 API
updated .gitignore with common ruby ignores including rbenv convention .ruby-version
added function to core.rb to support scrolling to collection view items by item and section
bumped the gem version to 0.9.167.pre2 and the framework version to 0.9.167
updated 0.9.167 changelog with details about collection view scrolling
Merge pull request #312 from jmoody/feat/0.9.x-collection-view-scrolling

adds client support for scrolling to item/section in UICollectionViews