Change version numbering of nvidia packages

[Lekensteyn]

nvidia-current-dev cannot be installed because 280.04-0~nattyubuntu4 seems not to fulfill the required version >= 280.04. This is caused by the tilde in it.

Proposal: use versions like 280.04-0-nattyppa1 because:

• 1-0- >= 1-0 where 1-0~ < 1-0
• Releases are alphabetical sorted, so 1-natty are considered newer than 1-maverick
• ppa indicates that it's a ppa version. We're ignoring the ubuntu text because we're not based on debian

Resources to consider:

• https://help.launchpad.net/Packaging/PPA/BuildingASourcePackage#Versioning
• http://www.debian.org/doc/debian-policy/ch-controlfields.html#s-f-Version
• http://people.canonical.com/~cjwatson/ubuntu-policy/policy.html/ch-controlfields.html#s-f-Version

Comments?