This is a bit artificial, as all image objects are still based on
the Evas.Image main class. The inheritance tree alone does not
give much information on what features are supported by which
class (eg. only Efl.Canvas.Image supports the file interface for
file_set).
Efl.Canvas.Snapshot and Efl.Canvas.Proxy are specialized
classes previously implemented as features of Evas.Image.
Note: this half of the work, as I suffered from a bad
merge and rebase with my work branch on top of master.
Jean-Philippe Andre