Prepare library for contributors

[jarda-svoboda]

Currently, the code is a bit hard to read for external contributors, so following steps need to be done:

• Make a code revision
• Comment functional parts
• Create a file with contribution instructions

[jacob-8]

I recommend a monorepo structure if you have multiple packages. Having to clone down three repos is a bit of a blocker to quick contributions. Thanks for the good work here!