customized placement of export banner and new properties added for fixed banners.

4 new properties added:
- one property to customize the export banner placement
- three properties for fixed export/pagination banners. For fixed banners the table displaying the list will be wraped into a div element (viewport). Using the viewport the table can be futher customize using css to have table with fixed header.


export.banner.placement= top | bottom (default) | both | null (if null then no banner will be displayed)

fixed.banners = true | false (default )
viewport.height = height for the viewport div. default height is 100%
viewport.class= name of a css class. default class name is viewport


This modifications are done against version 1.1.2-SNAPSHOT. I have run all the tests before adding my modification and 4 of them have failed. After implementing the new behavior i have run all the tests and same 4 tests have failed also. You can find attached test output.

I didn't implemented any test, because i'm not sure what to test.