[rancid] Disabling commands without altering rancid.types.base

[Howard Jones]

I have a few nexus 7000 switches where the contents of bootflash changes 
very regularly, causing spurious changes. For now, I've commented out 
some commands in etc/rancid.types.base, against the advice of the 
manpage. Is there a way to remove commands in rancid.types.conf for an 
existing device type?

# cisco-nx;command;nxos::DirSlotN;dir bootflash:
#cisco-nx;command;nxos::DirSlotN;dir debug:
#cisco-nx;command;nxos::DirSlotN;dir logflash:
#cisco-nx;command;nxos::DirSlotN;dir slot0:
#cisco-nx;command;nxos::DirSlotN;dir usb1:
#cisco-nx;command;nxos::DirSlotN;dir usb2:
#cisco-nx;command;nxos::DirSlotN;dir volatile: