- fix off-by-one bug in auto page size calculation

- removed duplicate output in pager info display
added the assert.js required to run slickgrid as it now contains internal assertion tests -- TODO: use a grunt task to remove these from the sources for production output library code

also added a jQuery.browser backwards compatibility addon as jQuery 1.9+ does not support $.browser any longer while some of our code still uses it (and replacing that by other solutions is deemed too much work for little result right now)
introduced the internal getColumnOffset() function to hide the code complexity where we now rigorously employ the column cache to deliver cell pixel offset values, replacing the loops in several places by a single lookup.

Also simplified the column cache into using a single columnPosLeft[] array storing both right/left edges (as they are the same) thus cutting down on the cache prepwork for each update. cache array columnPosRight[] is now obsolete and removed from the code.

Simplified the colspan using code as many conditional calculations were performed where a simple straight single calculation is perfectly equivalent.