#4662: Links updated

- They point to edges of objects (a bit complicated logics)
- Changed their width to look nicer, as well as arrow's width
- Changing cursor when moving mouse on item in graphView (experimental)
#4739: Add/edit annotations of any objects
#4662: Links have sharper arrows.

- Also changed the was arrows created.
#4389: Annotate in dirTreeView, #4764: fixed

#4389:
- Subclassed QFileSystemModel, added one column and connected it to
GraphModel
- When you edit annotation you add element to model, but set flag
isShown to false (in QMap), so that it is not shown on scene neither in
tableView. It is processed by MainWindow because it affects lots of
widgets.
- Set correct header data for tableView and SourceBrowser
#4764:
- Not proper cast of object, used Node class, but needed ObjectVisual +
check if they are links (because links don't have real polygon to
intersect with)
Also:
- When object added, it is also affected by filter immediately(on scene)
- Saving annotation while converting textblock/identifier
- Now converter saves links of object, not model
- When holding Ctrl and clicking on object we move to it in other views
#4667: Nicer binary data filter

It worked before, but now it helps you to type in binary data dividing
string by spaces.
#4723: Disable and move table's columns

- One column should always be enabled due to disappearing of headerView
if everything is hidden
#4723: Fixing build

- Always forget that it is case sensitive
#4766: Increased scene's keyboard logics

- If 2 nodes selected, connect them
- If 2 link selected, connect them
- If 2 any items selected (node+link), connect them
#4765: Added creating binary object from one byte
Merge remote-tracking branch 'origin/devel' into #4748-9

Conflicts:
	src/GraphModel.cpp
	src/GraphModel.h
	src/MainWindow.cpp
	src/src.pro