Added full Linux boot to regression-wally

Created by: slmnemo

Added logfile and overwrite variables to TestCase tuple to decouple log output from files regression searches. Searchfile added to testcase list format, creating tests format

[config, name, args, grepstr, log location]

We may prefer to add the overwrite to this tests format with the log location such that

[config, name, args, grepstr, [log location, overwrite]]

Instruction Limit is currently at 600M. Not sure if this is adequate for a full Linux boot.