grunt.util._ related enhancements

- use grunt.util._.uniqueId
  https://trello.com/c/cYjAXWok/69-use-grunt-util-uniqueid
- var _ = grunt.utill._
  https://trello.com/c/WrytMl4W
Moving bugs link to Trello
adding local.json to .gitignore

https://trello.com/c/ny2PdF6q
Removing init templates

https://trello.com/c/tQRBdcba
move ./.carnaby/tmp to .tmp

- tmpDir is now a config option:
- symlinks.common is now a config option
- symlinks.vendor is now a config option
- decoupling handlebars options

https://trello.com/c/cHOrI2h8
General API documentation revision.