Support various types of NVRAM variable parsing/extracting

[theopolis]

There is limited support or NVAR parsing/extraction. Support the other common types: VSS, VSS new, EFI, etc.

Support for regeneration of firmware after changing variables would be nice too!

[timevortex]

A lot of the logic around parsing and extracting these variables already exists in chipsec and you should be able to re-use a lot of that: https://github.com/chipsec/chipsec/blob/master/source/tool/chipsec/hal/uefi_platform.py

There's also a pull request on chipsec to add support for parsing Apple's NVARs as well: chipsec/chipsec#14

[NikolajSchlej]

Will be ported into UEFITool NE too, once I find enough time for it.

[startergo]

Will be ported into UEFITool NE too, once I find enough time for it.

Any information on how to extract NVRAM variables from Apple fd firmware? Either this tool or yours?