[core] Remove use of canonical_ptr
Remove all references to haccable_pointers
[hacc] Remove haccable_pointers (X* is in standard now)
[core] Abstract out command_from_string
[core vis] Move console into vis
[core] add char_listener imitating key_listener
[vis] more console work
[util] add Linked wrapping Linkable
[core] Add Receives_Output
Specify shaders inline in programs.  Not functional yet.
[hacc] new() macro allocates pointers
Shaders in programs use hacc new() macro