CA-122558: Removed FixLinkDelegate. Use System.Action instead.

Signed-off-by: Konstantina Chremmou <konstantina.chremmou@citrix.com>
Fixed column sizing issues on the Updates page.

Signed-off-by: Konstantina Chremmou <konstantina.chremmou@citrix.com>
Moved classes DiskInfo and OvfEventArgs and enums DeviceType and OvfEventType to
a different file to reduce a bit the size of the OVF.cs file.

Signed-off-by: Konstantina Chremmou <konstantina.chremmou@citrix.com>
Made XenOvfApi project use log4net for logging (before it was using own logging,
leftover from the time when the OVF wizards were a XenCenter plugin; the latter
has now been removed).

Signed-off-by: Konstantina Chremmou <konstantina.chremmou@citrix.com>
Added tooltip to the item of the "Filter by severity" drop down. Updated image;
adde placeholder image.

Signed-off-by: Konstantina Chremmou <konstantina.chremmou@citrix.com>
Moved constant "XenCenter.LastSeenServerVersion" from Updates.cs to IgnoreServerAction.cs
as it was only used in the latter class.

Signed-off-by: Konstantina Chremmou <konstantina.chremmou@citrix.com>
Refactoring: CanIgnore can be a "get" only property. Correction: dismiss new server
version alert from connections rather than ConnectionsManager.XenConnectionsCopy
(in accordance to dismissal of patch alerts).

Signed-off-by: Konstantina Chremmou <konstantina.chremmou@citrix.com>
CA-114482: Changed workflow of retrieving updates: the list of published updates
is downloaded and stored every time an update is performed (if manual all updates
are downloaded, if automatic only as per the user's choices). If there are available
updates, update alerts are generated if there are connected hosts and disappear
when the hosts are disconnected.

Signed-off-by: Konstantina Chremmou <konstantina.chremmou@citrix.com>
[CA-115418], [CA-123574]: Fixed issue where the Dismiss item on each alert row
was available for non-dismissible alerts. Fixed wrong enabled state of the top
ToolStripSplitbutton Dismiss on the alerts and the events page. Refactored code
calculating dismissability of alerts and dismissing them. Events list should be
multi-selectable.

Signed-off-by: Konstantina Chremmou <konstantina.chremmou@citrix.com>