Client side pagination feature.

This plugin enables client side pagination as requested in #1367.

Having pagination enabled, the grid renders only a configured number of records (defaults to 10). Via API methods, you can move to the next page, the previous page or specify a page you want to jump to. Currently, the user would have to build his own pagination controls outside the grid. But I would be willing to build a pagination bar into the grid if you decide to merge my feature.

This feature is obviously only useful, if the grid knows about the complete data set. You should not combine it with infinite scroll.