Fix #292 3.x support for mach_o_change
Fix #292 3.x support for mach_o_change

Tested with 2.5, 2.7 and 3.3 with install_name_tool chmod -x.

Use encode/decode for bytes/string transition.

madprog/virtualenv,techtonik/virtualenv,davidszotten/virtualenv,ionelmc/virtualenv,mykemunson/virtualenv,kissthink/virtualenv,francatore/virtualenv,ionelmc/virtualenv,Lyleo/virtualenv,Ivoz/virtualenv,bigplus/virtualenv,RAS-ViVa/virtualenv,Lyleo/virtualenv,Seha16/virtualenv,Ivoz/virtualenv,dstufft/virtualenv,kissthink/virtualenv,ionelmc/virtualenv,dstufft/virtualenv,jedie/virtualenv,davidszotten/virtualenv,bigplus/virtualenv,vvtam/virtualenv,haridsv/virtualenv,blueyed/virtualenv,jedie/virtualenv,haridsv/virtualenv,vvtam/virtualenv,mykemunson/virtualenv,RAS-ViVa/virtualenv,techtonik/virtualenv,blueyed/virtualenv,Seha16/virtualenv,madprog/virtualenv,francatore/virtualenv