MNT: Remove dependency on avscale
fslreorient2std currently calls avscale which is in the flirt project. To avoid circular project dependencies ( and simplify the code ) fslorient is now called instead.
Edited  by Matthew Webster
fslreorient2std currently calls avscale which is in the flirt project. To avoid circular project dependencies ( and simplify the code ) fslorient is now called instead.