Basic multi root API samples

This extension adds an entry to the status bar that shows the name of the currently active file. To exercise multi root APIs it:

only enables itself when more than one WorkspaceFolder is opened using workspace.workspaceFolders API
shows the name of the WorkspaceFolder the file is from (if any) using workspace.getWorkspaceFolder() API
updates when there are changes to the number of WorkspaceFolder via the workspace.onDidChangeWorkspaceFolders() API
registers a setting multiRootSample.statusColor with a scope of resource to configure a color per WorkspaceFolder to use for the status bar item

Running the example