Problem: Extending sign and foldcolumn below the text is confusing. Solution: Let the sign and foldcolumn stop at the last text line, just like the line number column. Also stop the command line window leader. (Christian Brabandt, closes #3964)
Problem: Not all white space difference options available. Solution: Add "iblank", "iwhiteall" and "iwhiteeol" to 'diffopt'.