CSAR file length is now correctly displayed on the CSAR details menu
Implemented DownloadCsarFileServlet
Extended ftl with downloadlink
Replaced file_size from String to long, refs #86
Merge pull request #129 from TKosch/86

Implemented DownloadCsarFileServlet, refs #86

* CSAR file length is now correctly displayed on the CSAR details menu
* Extended ftl with downloadlink
* Replaced file_size from String to long