Docs update to improve UX

[brimigs]

It would be great to have additional information in the readme to make the new user onboarding as simplistic as possible. This would include:

• hfuzz installation is a prereq for using this tool cargo install honggfuzz
• Add in a quick summary at the top of the readme on what a fuzz test is for user unfamiliar
• Add in a section for "how to use" that gives a UX walkthrough of the fuzz tester because using the tool without documentation isn't extremely intuitive