jquery.mobile.tabele.reflow.js: removed the display: table-row-group; css. Fixes 6583. This display property causes assistive technology like VoiceOver to no longer detect the table as a table. 

I apologize in advance for this pull request because I do not have Safari <= 5 and am therefore not able to reproduce bug 5380 - which this code was supposed to fix. However, the fix for 5380 is invalid because it directly causes the issue reported in 6583 in a lot of different browser and AT combinations.