Implement home screen with sort of kpi sections

[LeversonCarlos]

Current home screen is just the initial folder listing.
Should make this home screen with some kind of box sections.
Each one, listing top fives items. Clicking items, just open it normally.
Some of this kpis sections should be:

• Currently reading items
• Most recent items
• Top rated items
• Recomended items

Plus, we should have some kind of tools as:

• Refresh items (moving logic from startup engine somewhere else)
• Set comic root folder
• user guide (some kind of comic book manual)