Update HISTORY.md
`Node#getHTML()` now works on document fragments
Added unit tests to ensure `Node#getHTML()` works on document fragments
Tree: Fix inconsistencies when inserting nodes already in the tree.

This fixes two issues when inserting a node that already exists in the tree:

- Previously, the node was removed from its original parent silently before
  being reparented. Now we fire a `remove` event with {src: 'add'}.

- Inserting a node into the same parent with a new index could result in an
  off-by-one error. Now the desired insert position is maintained.
Merge branch 'tree-add' of git://github.com/rgrove/yui3 into dev-3.x
Build tree.
Merge branch 'patch-6' of git://github.com/ziggyism/yui3 into dev-3.x
Formatting and a tiny perf shortcut.
Build node-base.