great start on Remotes (data structure seems decent); now need to populate RemoteNodes with Remote branches;
minor cleanup; doc;
added RemoteInfo; added BranchComparison; minor cleanup and doc;
new Node classes; minor drag-drops for Branch and Remote node; doc;
added class structure which may be useful for future usage;
refactored GitPushAction into a new GitPush class;
added methods related to GitPush class;
minor refactorings; doc;
interface impl for LocalBranch drag/drop onto RemoteBranch;
minor refactors;
(future logic);
added HeadBranch and IsHead;
added RemoteBranch ContextMenu interface; Remote's HeadBranch has a gold-colored image;
added ability to Un-Track a remote-tracking branch;
Expand/Collapse buttons had been removed; (progress)
HeadBranch icon was a disfigured compared to normal branch icon;
on Node.TreeNode set, set TreeNode.Tag property;
fixes #20 Compare children; removed IsLocal, IsRemote properties;
Merge remote-tracking branch 'berger/left-panel/-main' into left-panel/-main

Conflicts:
	GitUI/FormPush.cs
	GitUI/RepoObjectsTree/ROT.Nodes.Branches.cs