Added 'cc' command to compare bytes with column hexdiff
Added r_print_hexdiff() public api
Added diff.from and diff.to eval configuration variables
Visual 'D' used to setup the visual diff offsets
Press 'c' to enable cursor in visual diff
Press '<tab>' to cycle between diff.from and diff.to
Use RCore's RNum from RConfig
Fix bug in r_core_read when io.va and sections used
Fix bugs in r_io_maps and io.va
Multiple files can now be opened and compared with mapping