Make result update more efficient

[jzaefferer]

On big job pages the update is rather slow. As @Krinkle said in #213:

"It does create a document fragment, though, that should be made more efficient by only returning the table html from the server. That way we don't have to have .load() it and .find() the table in order to compare the innerHTML."

Should do that.

[scottgonzalez]

We should just return HTML. There's no need to complicate it with JS templates.

[Krinkle]

Resolved with:

• 979693b job.js: Use $targetTable instead of querying the DOM again
• aca1805 job.js should keep refreshing even when everything is complete and "reset" happens.
• 86cb636 job.js: Add error handler to hide indicator and schedule next update

And today:

• a569c99 Page: Implement partial response support for JobPage