FEAT: additional info in build/test logs

[krzycz]

Sometimes, to investigate the build/test failure it might be useful to have more info about the build/test environment.

build log:

• version of the compiler and other tools
• version of the libraries, valgrind, etc.
• ...

test log (additional info may be optional / dumped only in case of test failure):

• version of the kernel
• are tests run with superuser privileges?
• testconfig.sh / envvars
• file system capacity (i.e. amount of PMEM, size of DAX device(s), etc.)
• number of CPUs/cores
• ...