Blender Git Loki

Depsgraph: Make node an owner of its name

The initial idea of using char pointer was to save some
memory since the dependency graph was kind of the one
with the main database.

Nowadays dependency graph should be separatable from the
main database and being self-sustainable.

Other issue which was caused by this pointer is the
re-tagging of operations during relations update: it is
possible to have node which as tagged for update but had
the owner of the name removed (i.e. driver or bone was
removed).