Update to jquery 1.4.2 and jquery-ui 1.8.1

[vipsoft]

Firefox regressions:

• @todo

IE regressions:

• IE8: drag and drop Flash content widget on Dashboard displays an anomaly and JS error ('null' is null or not an object)

Safari regressions:

• @todo

Opera regressions:

• @todo

[vipsoft]

(In [2159]) refs #1235 - update libs

[vipsoft]

(In [2160]) fixes #1062, refs #1235 - revert [1671] EmulateIE7 compatibility mode

[vipsoft]

(In [2165]) refs #1235 - fixes "null is null or not an object" error

[vipsoft]

(In [2208]) refs #1235 - workaround "null is null or not an object" error on IE by cloning and hiding the Flash during the drag operation

[matt]

great stuff! i did a quick test with chrome/ie8/opera and couldn't find any bug

[vipsoft]

(In [2298]) refs #1235