Remove View type parameter from DocumentType
auto merge of #1048 : ttaubert/servo/documenttype, r=jdm

This should fix #1046.
Handle th tag as HTMLTableCellElement. #1060
auto merge of #1061 : saneyuki/servo/th, r=larsbergstrom
Implement HTMLTableDataCellElement & HTMLTableHeaderCellElement.
auto merge of #1063 : saneyuki/servo/th, r=jdm
Add line breaks for readability.
Rename the element field of the DOM Node hierarchy.

See #924
Auto-generate some binding codes for HTMLElement, Element, CharacterData.
auto merge of #1064 : saneyuki/servo/cleanup, r=jdm

This pull request is based on #1063.