Create full documentation.

[stepanzubkov]

I prefer docs in markdown format, so I want to use it for cc-api docs.

• [x] Rewrite README
• • [x] Add information about license
• • [ ] Add contribution mini-guide
• • [x] Rewrite deploy guide
• • [ ] Add logo (optional)
• • [x] Add information about clients (cc-cli, cc-web)
• [x] Add API docs in docs/ folder
• • [x] Describe all url/ methods
• • [x] Describe all paste/ methods
• • [x] Add examples (curl + maybe python)
• • [x] Describe Url and Paste models.
• • [ ] Mini-guide for contributors, that describes code structure and code style

All docs should be initially written in English and later translated to Russian. Maybe other languages, if I find translators.