minor fixes in qemu.nbd_mount
Double checck string load in qemu.clear
Clean up qemu-img commands
Adding DNS zone file parser
Doing a little cleanup
Merge pull request #3753 from techhat/dnsutil

Adding DNS zone file parser
Add -- to parted commands to fix escape errors and fix mkfs
Reformat qemu functions to be more granular and start on bootstrap
Don't override, instead extend `module_dirs`. Fixes #3754.
Try fixing travis zmq import errors.
No user interaction.
Some more of no user interaction.
Corrected apt call.
Use sudo.
Install mode deps.
How about the full path to the python binary?
Also install mock. Use the correct python version.
Cleanup. Pip should update packages and also use mirrors.
Don't use `-U` with pip. Makes M2Crypto re-install and fail.
Commented out test case which is failing since 209c5660105e3c042a39a93c3d9a4aa5a77de2df. @vlaci could you have a look please?