Content Model Fidelity improvement 12: parse and save format from TR element

[JiuqingSong]

From previous change (#1781) table row can have its own format object. Now we parse format from TR and save the format into this object.

For now we only support saving one format of TR: backgroundColor.

Other fixes in this change:

• For container with "display: inline-block", it is also possible to be treated as FormatContainer
• When process Table, do not copy margin styles into table since it is table will not inherit these styles
• Allow cache TR element, and use it when write back
• Support backgroundColor in link
• Support display in FormatContainer
• When adjust selection for word, also clone link and code decorator if any
• Change demo site to show TableRow