CP-8866:Develop for Resource Statistic Feature on XenCenter

Based on the requirements draft and discussed solution, develop the prototype for Resource Statistic Feature part on XenCenter, that is, provide the export to Excel and CSV functionality with required data sets,by accessing the XenCenter cache.
Signed-off-by: Cheng Zhang <cheng.zhang@citrix.com>
All the objects in the generated report are listed in random order. They need to be sorted either here, at compilation time, or at export time. (Here might be easier so that you don't have to do it separately for csv and xls).

All objects have a built-in Compare function, so just calling .Sort on a list of objects will sort them. So I suggest something like (not tested!):

var hosts = new List<Host>(Connection.Cache.Hosts);
hosts.Sort();
foreach (Host host in hosts)

(and then insert them at the right-hand end of the list six lines below here).