add a manual test case for ZSS-589
fix ZSS-589 Hidden rows are still displayed in IE
add manual test case for zss-617
fix ZSS-617 After spreadsheet loads a book, a mask is blocking the sheet
add performance testcase
add test file for zss-589
ZSS-612: Don't allow sort book dialog in ZSS app
Update release-note for ZSS-612
tune performance test
Merge commit '784ab0b9a05e86d404b36ecc5e3ce02a33417bfd' into 3.5
Merge branch '3.0' for zss-617

importer should import custom width flag.
Conflicts:
	zss/src/org/zkoss/zss/ui/Spreadsheet.java
Merge branch 'origin/3.0' for zss-612, performance test

Conflicts:
	zkdoc/release-note