Merge pull request #57 from luisrudge/master

Added '[x] Select all' option.
Added gitignore for project files.

Added gitignore for project files.
Normalize prop access a la http://api.jquery.com/removeProp/
* Use prop("property", false), rather than removeProp("property")
* Use prop("selected", true), rather than prop("selected", "selected")
Made single selection checking work properly so .val() returns correctly
Removed browser sniffing for IE and use :selected pseudoselector everywhere
Merge pull request #58 from programcsharp/master

Normalize prop access
Added selectAll, added demos, cosmetics.

Added selectAll option and demos. Further cosmetics, comments etc. .