Remove access to free'd memory in cmd_free
Remove access to free'd memory in cmd_free

Fixes GitHub issue #73

cauchycui/webdis,cauchycui/webdis,boothj5/webdis,nicolasff/webdis,nicolasff/webdis,boothj5/webdis,nicolasff/webdis,boothj5/webdis,mrkeng/webdis,cauchycui/webdis,mrkeng/webdis,cauchycui/webdis,nicolasff/webdis,mrkeng/webdis,mrkeng/webdis,nicolasff/webdis,boothj5/webdis