Network Scan Folder does not work [#318 responsible:none state:fixed]

Updated so that SOLA can connect to a network share using NTLM credentails.
Also enhanced the feature so that filters can be used to only display
specific documents as well as allowing files from all subfolders of the
Network Share that match the filters to be displayed.

Also updated the SharedFolderCleaner EJB to use the new file share functionality.
Improve performance of Server Image Preview [#320 responsible:none state:fixed]

Updated so that server image previews are cached on the client.  To prevent
images from becoming stale, the last modified date is pre-pended to the
file name. This will ensure the thumbnail is updated if the source image is
updated.
Added exception management when when Network Scan Folder is unavailable