Bug fixes and compatibility

What's Changed

• Make it possible to exit if rocket is not connected by @mgunyho in #1
• Add 'make run' command by @mgunyho in #2
• Building on Ubuntu 20.04 works now, required LDLIBS were added to Makefile

New Contributors

• @mgunyho made their first contribution in #1

Full Changelog: v0.2.0...v0.2.1