Made background of graphItem's name

Using HTML5 in QGraphicsTextItem.
Added property model in GraphItem

1. Connected selectionChanged() from scene to refreshModel in
ui->propTreeView
2. Some random stuff goes into GraphItem's model, someone should
organize it.
3.
Set default size of scene

Now it has some size, but wheel event doesn't work.
Imroves

1. Better GraphView: if "SHIFT" is pressed, then you can select multiple
item, else you drag the area of view.
2. Better treeView: now on clicking one item in graph will scroll you to
it's place.
3. Improved GraphItem's model
propTreeView improve.

Now propTreeView will not show anything if nothing is selected.
Also added shortcuts for "Zoom In"(+) and "Zoom Out"(-).
Added comments
added comments
Added comments
Merge branch 'develop' of https://github.com/Zo0MER/graph_editor into develop
Modified commit
commit!
fix bug with connect
fixed bug with blob
Fixed blob's change

Now it expands as you add text in comment.
fixed bug with blob
Fixed bugs with selection edges and blobs of commits
Merge branch 'develop' of https://github.com/Zo0MER/graph_editor into develop

Conflicts:
	graph_editor.pro.user
	graphcomment.cpp
	graphcomment.h
better use graphicsitem_cast
Fixed .gitignore

Actually *.pro.user isn't so needed to be synced I think.
Wuaha-ha

Delete *.pro.user
Replaced dynamyc/static_cast with qgraphicsitem_cast
Merge branch 'develop' of https://github.com/Zo0MER/graph_editor into develop