Internet Explorer 8 compatibility

In Internet Explorer 8, reserved keywords kan not be used in dot syntax.

By replacing `$tags.for` and `$tags.if` with `$tags['for']` and `$tags['if']` respectively, `jsviews` will also work in Internet Explorer 8.

Why is this important? Because as of today, Internet Explorer 8 still has the largest market share with 21.5% (July 2014).

http://www.netmarketshare.com/browser-market-share.aspx?qprid=2&qpcustomd=0