Update README readthedocs.io for v0.2

update the https://axolotl.readthedocs.io/en/latest/ so the documentation is much better

[ ] Explanation about the Axolotl
[ ] Tell the flow work with axolotl
[ ] 1. Start with init the project
[ ] 2. Explanation about the directory structure
[ ] 3. Add Host Identity
[ ] 4. Explanation about Host Identity, How to input, and key explanation
[ ] 5. Add Vulnerability Finding
[ ] 6. Explanation about Vulnerability Finding, How to input, and key explanation
[ ] 7. Status Flow
[ ] 8. Change the status
[ ] 9. Lookup All Host
[ ] 10. Lookup All Vuln
[ ] 11. Host Information
[ ] 12. Simple Statistic
[ ] Simplify the README.md

k1m0ch1 / axolotl