mini-graph: Remove redundant constructor argument

No user is passing 'points' at construct time so lets remove it.
mini-graph: Make 'ymax' prop public
Sidebar handles its content for properties view

Instead of Properties class setting up all the UI of sidebar for its own
view, Sidebar now handles that itself. This implies moving of most of
this UI setup to a .ui file.
mini-graph: Remove now redundant constructors