Disable non-relevant context menus

The Expand Folder and Expand All Folders context menus should be disabled for uploads since they do nothing.

The only way to determine if 'Expand Folder' or 'Expand All Folders' should be enabled is to enumerate the selection/entire queue and check to make sure at least one of the entries is a download transfer type, however this process is slow and depending on the number of entries in the queue it isn't practical to perofrm this check due to performance issues.