improvements to DataType.Date.parse

- return Date object when passed one (fixes #2530058, closes #2530059)
- accept timestamp as number or string
- remove obsolete workaround in validation
Avoid processing columns if there aren't any to allow empty tables.
Merge remote-tracking branch 'upstream/master'
clean up var declaration for name argument. Fixes #2531867.
build node
Merge remote-tracking branch 'upstream/master'
Merge branch 'master' of git://github.com/yui/yui3
fixes #2532134 Added sort test to cover Date, Number and String data types with case sensitive sort available by setting a caseSensitive param to true on the table column.
ref #2532134 Changed Y.Lang.isString() to typeof() === 'string' to improve performance, and added comment to component history.
ref #2532134 Updated documentation with new caseSensitive attribute details. Updated default order of test data.
ref #2532134 Updated documentation added a short paragraph to the 'Column sorting' section
Merge branch 'master' of git://github.com/yui/yui3
Added yui-soon
Add manual tests for histograms.
Merge remote-tracking branch 'upstream/master'
Merge branch 'master' of git://github.com/yui/yui3
Added wrapper functions around setImmediate and setTimeout.
Merge branch 'master' of git://github.com/yui/yui3
Merge branch 'master' of git://github.com/yui/yui3
Merge branch 'master' of git://github.com/yui/yui3