cubicweb #4172701 Fix Binary.__eq__ implementation [validation pending]

Binary.__eq__ implementation is broken, it just forgets to compare binary contents:

http://hg.logilab.org/master/cubicweb/file/cubicweb-version-3.18.5/__init__.py#l125

Since __eq__ is used by the editcontroller to check for changes, this explains why a file content can't be updated anymore with standard edition forms.

prioritynormal
typebug
done in3.18.6
load0.100
load left0.000
closed by#a84922befb89 Fix Binary.__eq__ (closes #4172701)