word level diff

[wkpark]

this is a quick hack to support word level diff with viewType = 2 param.

    viewType:2,
    contextSize: 3

Please see http://moniwiki.kldp.net/diff.html

[srgsanky]

Is viewType=2 still supported? The code tends to default to 0 if we use 2. See https://github.com/cemerick/jsdifflib/blob/master/diffview.js#L54

[Sivolen]

I encountered such a problem that in those places where characters have changed, it draws lines without spaces like "destination10.0.1.96" i fixed it, changed the regex ([^\S]+|[a-zA-Z0-9_-]+|.)(?:(?!<)[^\S\s])? I think it looks better