Completely overhauled tool.
* scanless can now be used properly as a library.
* Proper class structure with a reusable session.
* Randomizes user strings.
* Fixed a few scanners while updating.
* Better error checking / custom exceptions.
* Minimized a lot of code.
* Generates output nicely using nmap service names.
* CLI flow improvements using scanless as a library.
* Fixed license trove classifier is wrong in setup.py
* Tool is Python 3.6+ now and this is specified.
* Bumped major version.