make book use shared toc-node code
make gh-book pointer extend the common pointer code
restructure folder model to match book

- changing title of content changes it on the content (no override
titles)
- changing title marks folder as dirty
update the URL for new folders
clear dirty bit on folder save
make a pointer when dropping to folder
replace [0].innerHTML with .html()
remove whitespace
repalce ! with not keyword
Merge branch 'master' into atc-make-book-use-shared-toc-node

Conflicts:
	scripts/gh-book/toc-pointer-node.coffee
	scripts/models/content/book.coffee
make dfs/bfs and getChildren optional

Folders to not use TocPointerNode so they do not have a tree structure
Merge branch 'master' into atc-restructure-folder

Conflicts:
	scripts/gh-book/toc-pointer-node.coffee
	scripts/models/content/book.coffee
Merge branch 'master' into atc-new-url-for-folder

Conflicts:
	scripts/gh-book/toc-pointer-node.coffee
	scripts/models/content/book.coffee
Merge pull request #102 from oerpub/atc-dfs-optional

Atc make dfs/bfs and getChildren optional (Should not affect gh-book)
Merge pull request #110 from oerpub/avoid-running-two-updaters

Avoid the exception where two updaters run at the same time
Merge pull request #92 from oerpub/atc-make-book-use-shared-toc-node

Atc make book use shared toc node (Should not affect gh-book assuming other PRs merge)
Merge pull request #94 from oerpub/atc-restructure-folder

Atc restructure folder code (Should not affect gh-book; depends on PRs)
Merge pull request #99 from oerpub/atc-code-cleanup

Atc code cleanup
Merge branch 'master' into atc-new-url-for-folder
Merge pull request #96 from oerpub/atc-new-url-for-folder

assorted Folder updates (Should not affect gh-book; depends on PRs)