fileDownload session support

[loveapple]

Change log:

• add check session value function.

  • session value check function use ajax to get server values and sample of response body from server side.

    {"resultCode":"SUCCESS","errorMsgs":null,"code":",1411101372971"}

• the session key can be set in application on the server side.
  • I didn't delete variable name of [cookieXxxx] in this version, and use "cookieValue" for check session value.

Why hacks it

When multiple to download file in a same session, the download of modal window wil be not appear, because the cookie value will be changed by other operation. So I use the HTTP session to save multiple download status values. Of caurse, May be delete be used download status from session, but didn't implemente it in this version.