Option to don't copy libraries and tools to case folder

[lfcnassif]

This could decrease RAM usage by IPED-Triage Linux distribution used in triage scenarios where the case is created in a ram drive in some configurations.

Maybe this could also be the new default mode in 4.0.0, and user could use the --portable option to copy libs and tools to case folder. I plan to create a simple "create case gui" in #23 from where cases could be opened without having the libs/tools.