implement new "EasyShell View" for selected resources modifications

[anb0s]

EasyShell executes commands with selected resources (files, folders, etc.) immediately.

Sometimes we want to ajust (add, remove etc.) the selections from "Open Resource" dialog or "Project Explorer" before executing commands.

Threfore EasyShell should provide new view that can be used as "virtual command" in "EasyShell" menu or as entry in "Open Resource" dialog under "Show In" or/and "Open With" menu.

[anb0s]

related to #164