Error while creating user account

[Moises Henriquez]

When creating the intial user account, the installer assumes GID and UID 1001 are available. Some probing should be done to verify and logic added to reach the next available UID and GID.

This issue is only problematic when installing a LIVE CD and the live environment has existing uid and gid 1001.

Offending code: https://bitbucket.org/VLCore/vinstall/src/c754355b869c70176d1d8bd25a885fa35ffe5e03/vinstall/backend/users.py?at=master&fileviewer=file-view-default#users.py-59